Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2025
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Securities and Shareholder Matters On March 6, 2023, a putative class action was filed in the United States District Court for the Middle District of Florida by a shareholder of the Company. The action was consolidated with another action and the consolidated case is now captioned In re Fidelity National Information Services, Inc. Securities Litigation. A lead plaintiff has been appointed, and a consolidated amended complaint was filed on August 2, 2023. The consolidated amended complaint names the Company and certain of its current and former officers as defendants and seeks damages for alleged violations of federal securities laws in connection with our disclosures relating to our former Merchant Solutions segment, including with respect to its valuation, integration, and synergies. On September 30, 2024, the court denied the defendants' motion to dismiss, and the case therefore has moved into the discovery phase. We intend to vigorously defend this case, but no assurance can be given as to the ultimate outcome. On April 27, 2023, a shareholder derivative action captioned Portia McCollum, derivatively on behalf of Fidelity National Information Services, Inc. v. Gary Norcross et al., was filed in the same court by a stockholder of the Company. Subsequently, that stockholder dismissed the suit without prejudice and sent a demand pursuant to Georgia Code § 14-2-742 (the "McCollum Demand"). Another stockholder, City of Hialeah Employees' Retirement System, sent a similar demand (the "Hialeah Demand"), and three other stockholders, City of Southfield Fire and Police Retirement System, Young Family Living Trust, and Michele Luthin, also subsequently sent similar demands (the "Southfield Demand," the "Young Demand," and the "Luthin Demand," respectively). The Southfield Demand was subsequently withdrawn. The demands claim that FIS officers and directors violated federal securities laws and breached fiduciary duties, including with respect to the valuation, integration, and synergies of our former Merchant Solutions segment, and they demand that the Board investigate and commence legal proceedings against officers and directors in connection with the purported wrongdoing. On August 25, 2023, the Board established a Demand Review Committee to consider the McCollum and Hialeah Demands and any related demands that are received (such as the Young Demand and the Luthin Demand) and make recommendations to the Board with respect to the demands. The Demand Review Committee has hired independent counsel. The Board has made no final decision with respect to the demands and has not rejected the demands. On October 18, 2023, a shareholder derivative action captioned City of Hialeah Employees' Retirement System v. Stephanie L. Ferris et al. (the "Hialeah Action") was filed in the same court by the stockholder that previously had sent the Hialeah Demand. The complaint in the Hialeah Action, which names certain of the Company's current and former officers and directors as defendants (the "Individual Defendants"), seeks to assert claims on behalf of the Company for violations of federal securities laws, breach of fiduciary duty, unjust enrichment, and contribution and indemnification, including with respect to the valuation, integration, and synergies of our former Merchant Solutions segment. On March 29, 2024, the Company and the Individual Defendants filed a motion to stay or dismiss the action without prejudice pending the completion of the Board's consideration of the demands (the "Motion to Stay"), and the Individual Defendants concurrently filed a separate motion to dismiss (the "Individual Defendants’ Motion to Dismiss"). On March 21, 2025, the court granted in part and denied in part the Motion to Stay, and denied the Individual Defendants' Motion to Dismiss. The Individual Defendants filed answers to the complaint on April 29, 2025, and the case is partially stayed pending completion of the Demand Review Committee's investigation. On October 22, 2024, another shareholder derivative action was filed in the same court by the stockholder who previously sent the McCollum Demand, captioned Portia McCollum, derivatively on behalf of Fidelity National Information Services, Inc. v. Gary Norcross et al. (the "McCollum Action"). The complaint in the McCollum Action, which names certain of the Company’s current and former officers and directors as defendants, seeks to assert claims on behalf of the Company for violations of federal securities laws, breach of fiduciary duty, aiding and abetting breach of fiduciary duty, waste, and unjust enrichment, including with respect to the valuation, integration, and synergies of our former Merchant Solutions segment. On November 7, 2024, the court entered an order staying the McCollum Action. Indemnifications and Warranties The Company generally indemnifies its clients, subject to certain limitations and exceptions, against damages and costs resulting from claims of patent, copyright, or trademark infringement associated solely with its customers' use of the Company's solutions. Historically, the Company has not made any material payments under such indemnifications but continues to monitor the conditions that are subject to the indemnifications to identify whether it is probable that a loss has occurred, in which case it would recognize any such losses when they are estimable. In addition, the Company warrants to customers that its software operates substantially in accordance with the software specifications. Historically, no material costs have been incurred related to software warranties, and no accruals for warranty costs have been made.