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Investment Securities - Additional Information (Details)	9 Months Ended
	Sep. 30, 2025 USD ($) Security	Dec. 31, 2024 USD ($) Security
Schedule Of Available For Sale Securities [Line Items]
Equity securities, at fair value	$ 4,518,000	$ 4,439,000
Tax rate used to calculate tax-equivalent yields (in hundredths)	21.00%
Percentage investment book value exceeds stockholders' equity (in hundredths)	10.00%
Debt securities, available-for-sale, restricted	$ 537,300,000	$ 632,900,000
Number of securities in unrealized loss positions | Security	502	557
Available-for-sale, 12 months or longer, Fair Value	$ 914,868,000	$ 1,001,277,000
12 months or longer, unrealized losses	153,515,000	193,568,000
Held to maturity securities, 12 months or longer, unrealized losses	$ 0	$ 0

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