Subsequent Event	3 Months Ended
Mar. 31, 2024
Subsequent Events [Abstract]
Subsequent Event	Note 10 - Subsequent Event On April 1, 2024, Synovus transferred $3.42 billion of mortgage-backed securities from available for sale to held to maturity, and AOCI included a pre-tax unrealized loss of $708.5 million on the investment securities at the date of the transfer. Transfers of investment securities from AFS to HTM are non-cash transactions and are recorded at fair value. Unrealized losses at the date of transfer of these investment securities continue to be reported in AOCI and are amortized into interest income on a level-yield basis over the remaining life of the investment securities. This amortization will offset the effect on interest income of the amortization of the discount resulting from the transfer recorded at fair value.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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