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Securities, Available for Sale (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt securities, available-for-sale [Abstract]
Amortized cost	$ 1,607,983		$ 1,615,078
Unrealized gains	63		47
Unrealized losses	(189,575)		(184,267)
Estimated fair value	1,418,471		1,430,858
Allowance for credit losses on AFS securities	0		0
Gross realized gains	0
Gross realized losses	0	$ 5,000
Gain recognized on sale of previously written-off security	2,300
U.S. Treasury [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	133,442		133,302
Unrealized gains	0		0
Unrealized losses	(8,759)		(8,278)
Estimated fair value	124,683		125,024
Federal Agency [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	248,375		248,384
Unrealized gains	0		0
Unrealized losses	(35,071)		(33,644)
Estimated fair value	213,304		214,740
State & Municipal [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	96,054		96,251
Unrealized gains	1		11
Unrealized losses	(10,022)		(9,956)
Estimated fair value	86,033		86,306
Mortgage-Backed, Government Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	387,479		399,532
Unrealized gains	3		7
Unrealized losses	(45,461)		(44,264)
Estimated fair value	342,021		355,275
Mortgage-Backed, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	71,036		74,281
Unrealized gains	10		14
Unrealized losses	(7,520)		(7,302)
Estimated fair value	63,526		66,993
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	452,853		452,715
Unrealized gains	49		15
Unrealized losses	(50,135)		(48,257)
Estimated fair value	402,767		404,473
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	170,293		162,171
Unrealized gains	0		0
Unrealized losses	(26,034)		(25,100)
Estimated fair value	144,259		137,071
Corporate [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	48,451		48,442
Unrealized gains	0		0
Unrealized losses	(6,573)		(7,466)
Estimated fair value	$ 41,878		$ 40,976
Loss on the write-off of an AFS debt security		$ 5,000

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- Definition

Amount of realized gain on sale of previously written-off investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ References

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-Topic 320
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