Business Combinations	3 Months Ended
Business Combinations	Mar. 31, 2026
Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]
Business Combinations	Business Combinations On August 1, 2024, the Company completed its previously announced acquisition of Macatawa Bank Corporation (“Macatawa”), the parent company of Macatawa Bank. Pursuant to the terms of the merger, each common share of Macatawa outstanding at the time of merger was converted into the right to receive 0.137 shares of Wintrust common stock, with cash paid in lieu of fractional shares. As a result, the Company issued approximately 4.7 million shares of common stock, the fair value of consideration paid was $499.3 million. Macatawa operates full-service branches located throughout communities in Kent, Ottawa and northern Allegan counties in the state of Michigan. Macatawa offers a full range of banking, retail and commercial lending, wealth management and ecommerce services to individuals, businesses and governmental entities. As of August 1, 2024, Macatawa had fair values of approximately $2.9 billion in assets, $2.3 billion in deposits and $1.3 billion in loans. In conjunction with the acquisition, the Company recorded $53.7 million discount on acquired loans, $33.5 million discount on securities and recorded total intangibles of $253.0 million. As of the first quarter of 2025, the purchase accounting was finalized and is no longer subject to change.

The entire disclosure for business combination.

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WINTRUST FINANCIAL CORP 10-Q