Appeal from the Circuit Court of Cook County. Honorable Richard J. Billik, Judge Presiding.
 The opinion of the court was delivered by: Justice Gallagher
 This appeal involves the statutory authority of the Suburban Cook County Tuberculosis Sanitarium District (the District) to sell 24" acres of its 36 acres of land in Hinsdale without the approval of the Board of Commissioners of Cook County (the County Board). On cross-motions for summary judgment, the circuit court granted the District's motion, ruling that it had implied authority to sell the property under the Tuberculosis Sanitarium District Act (70 ILCS 920/1 et seq. (West 2002)) (the Act). For the reasons stated herein, we affirm the judgment of the circuit court.
 The Suburban Cook County Tuberculosis Sanitarium facilities in Hinsdale include a functioning hospital and a parking lot that together cover approximately 12 acres of the 36-acre parcel. RM Health Providers (RM) currently leases the hospital from the District and provides health care services in that facility. On June 28, 2002, the District agreed to sell the remaining 24" acres of property at the southeast corner of 55th Street and County Line Road in Hinsdale to Edward R. James Partners (James Partners) for $15.25 million. That portion of the property included several residences, a parking facility and vacant land. James Partners was later succeeded in interest by Hinsdale Meadows Venture, which plans to build 36 single-family homes on the property. After the sale was finalized in October 2002, Hinsdale Meadows Venture arranged for demolition of the existing structures on the property.
 On April 7, 2003, the People of the State of Illinois, through Cook County State's Attorney Richard Devine, and Cook County (collectively, the County) filed a complaint against the District, James Partners and Hinsdale Meadows Venture in quo warrantor, challenging the District's power to sell the property and also seeking injunctive or declaratory relief.*fn1 The County contended that the land was public property and that by statute, only the County Board had the authority to sell the property if the District found the sanitarium facilities were no longer needed for treatment of tuberculosis patients.
 The District responded that it had the authority to sell the property without the County Board's cooperation or approval. The District also raised the affirmative defense of laches, contending that on July 24, 2002, the District's president, Terrance Carr, sent a letter to County Board president John Stroger informing the County Board, inter alia, of the District's plans to sell the 24"-acre parcel. In the letter, Carr stated that the District had negotiated the sale of the excess property that was "not required for the District to carry out its [tuberculosis] treatment mission." The County does not dispute Carr's letter to Stroger but asserts that the correspondence did not provide sufficient details about the pending sale.
 In a deposition, Carr stated he had been president of the District's board of directors since 2000. Carr said that the District wanted to lease or sell the property because it was vacant land and board members were concerned that the District would be liable for injuries on the property. Carr stated that the two single-family residences, townhouses, personnel building and garage on the 24"-acre parcel were not used for the treatment of tuberculosis patients, and that the District had unsuccessfully queried various health care organizations and governmental bodies about their interest in purchasing the land.
 Carr testified that the hospital and facilities on the Hinsdale property are necessary to treat tuberculosis patients and that the District did not recommend that those facilities be closed. When asked about a 1996 newspaper article reporting that the hospital had stopped admitting patients with the exception of the ventilator support unit, Carr replied that the hospital did not stop in-patient admissions for tuberculosis patients and that the facility maintained one intensive care room and two additional rooms for that use. Carr stated that Stroger did not respond to his letter until February 2003, when Stroger telephoned Carr and told him that the District lacked the legal authority to sell the property.
 The record also includes the deposition testimony of Dr. James Gallai, who has treated tuberculosis patients at the Hinsdale facility and who serves as the District's clinical director and also is a consultant to physicians in Cook County on the topic of tuberculosis. Dr. Gallai testified that while tuberculosis sanitariums historically have been located on large parcels of land to isolate the patients from the rest of the community, and while the contagious disease generally has warranted the patients' isolation from the general population, physicians now treat the condition with various antibiotics.
 Dr. Gallai testified the Hinsdale facility is necessary to treat tuberculosis as a form of bioterrorism, noting that a tuberculosis outbreak in New York City in the early 1990s caused between 3,000 and 4,000 tuberculosis cases per year for several years. When the District leased the hospital facility to RM, Dr. Gallai recommended that several beds remain available for treatment of tuberculosis patients. The three hospital rooms set aside for tuberculosis patients at the Hinsdale facility feature negative air pressure to keep air inside the room. Dr. Gallai noted that six outpatient tuberculosis facilities, including a mobile clinic, operate in the Chicago suburbs. Dr. Gallai stated that in the year or two prior to his deposition, one or two pediatric cases required in-patient care at one of the area tuberculosis facilities, and another patient with "active" tuberculosis required immediate psychiatric care. Dr. Gallai stated that those patients were already at another facility when their treatment for tuberculosis became necessary and, therefore, the Hinsdale facility was not used for treatment of those patients. Dr. Gallai stated that had those patients been admitted to the Hinsdale facility, he, as opposed to a RM staff member, would have treated them. Dr. Gallai stated that no tuberculosis patients had been admitted to the Hinsdale facility in the last three years, and he did not know if any were admitted in the four or five years before that. Dr. Gallai stated that the District has never recommended closing the Hinsdale facility.
 The parties filed cross-motions for summary judgment on the issue of the District's authority to sell the property. The County contended that when the District decided to sell the property, it made a de facto finding that the property was no longer needed to serve residents suffering from tuberculosis and that such a finding vested the County Board with authority to determine the use of the sanitarium facilities. The County asserted that as a non-home-rule unit of government, the District has only the powers enumerated in the Act or those that arise by necessary implication, and the County pointed out that the Act's only reference to the sale of property (70 ILCS 920/5.2 (West 2000)) indicates that such a transaction requires the County Board's approval. The County also argued that the defense of laches is only available against the government in certain circumstances.
 The District attached to its motion for summary judgment Carr's affidavit detailing its ownership of real estate in several communities and its sale of those properties without the County Board's approval.*fn2 Also attached to the District's motion was a June 1, 1999, letter in which the District informed the County Board that the District was "in the process of discussing the ideas and plans of several health care organizations for the development of a Continuing Care Retirement Community" on approximately 24" acres of the Hinsdale property. Carr's affidavit stated that the District unsuccessfully attempted to market the property to various health care organizations.
 In a written opinion, the circuit court granted the District's motion for summary judgment, finding that no genuine issue of material fact existed that the District had the implied authority under the Act to sell the property. The court noted that the District continues to own approximately 12 acres of land on the parcel and operates an in-patient sanitarium facility. The court also held that the County was estopped from attempting to void the sale because it did not timely assert its claim of the right to approve the transaction. The court denied the County's motion for summary judgment and its motion to dismiss the District's laches defense and entered summary judgment in favor of the District. The circuit court did not address the merits of the County's request for injunctive relief because the parties agreed not to physically alter the property pending the resolution of the District's authority to sell the land.
 On appeal, the County contends that the circuit court erred in granting summary judgment to the District because the District did not follow the Act's provisions governing the disposal of unused real estate. The County asserts that the Act does not grant to the District the authority to sell the property, either expressly or by implication, and that the County Board is to determine the use of the sanitarium facilities. The County also argues that the District's affirmative defense of laches does not apply.
 Summary judgment is appropriate where the pleadings, depositions, admissions, affidavits and exhibits on file demonstrate that there is no genuine issue of material fact and that the moving party is entitled to judgment as a matter of law. 735 ILCS 5/2-1005(c) (West 2002); General Casualty Company of Illinois v. Carroll Tiling Service, Inc., 342 Ill. App. 3d 883, 889, 796 N.E.2d 702, 706-07 (2003). Where, as here, the parties have filed cross-motions for summary judgment, they agree that no factual issues exist and that the case presents only the need for the resolution of legal issues; however, this court must determine for itself that no factual issues exist that would preclude summary judgment, and, if such factual issues are absent, the court may determine the issues presented as ...