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Securities, Available for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Debt securities, available-for-sale [Abstract]
Amortized cost	$ 1,641,356		$ 1,641,356		$ 1,743,882
Unrealized gains	8		8		38
Unrealized losses	(242,332)		(242,332)		(216,695)
Estimated fair value	1,399,032		1,399,032		1,527,225
Allowance for credit losses on AFS securities	0		0		0
Gross realized gains	0	$ 0		$ 0
Gross realized losses	0	$ 0	4,500	$ 0
U.S. Treasury [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	133,160		133,160		132,891
Unrealized gains	0		0		0
Unrealized losses	(11,565)		(11,565)		(11,233)
Estimated fair value	121,595		121,595		121,658
Federal Agency [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	248,392		248,392		248,419
Unrealized gains	0		0		0
Unrealized losses	(44,636)		(44,636)		(42,000)
Estimated fair value	203,756		203,756		206,419
State & Municipal [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	96,449		96,449		97,036
Unrealized gains	0		0		5
Unrealized losses	(13,164)		(13,164)		(14,190)
Estimated fair value	83,285		83,285		82,851
Mortgage-Backed, Government Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	412,257		412,257		454,177
Unrealized gains	0		0		9
Unrealized losses	(61,231)		(61,231)		(54,675)
Estimated fair value	351,026		351,026		399,511
Mortgage-Backed, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	74,812		74,812		81,844
Unrealized gains	6		6		15
Unrealized losses	(10,076)		(10,076)		(7,676)
Estimated fair value	64,742		64,742		74,183
Collateralized Mortgage Obligations, Government-Sponsored Enterprises [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	463,436		463,436		498,021
Unrealized gains	2		2		9
Unrealized losses	(63,389)		(63,389)		(59,473)
Estimated fair value	400,049		400,049		438,557
Collateralized Mortgage Obligations, U.S. Government Agency Securities [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	164,418		164,418		171,090
Unrealized gains	0		0		0
Unrealized losses	(31,056)		(31,056)		(21,284)
Estimated fair value	133,362		133,362		149,806
Corporate [Member]
Debt securities, available-for-sale [Abstract]
Amortized cost	48,432		48,432		60,404
Unrealized gains	0		0		0
Unrealized losses	(7,215)		(7,215)		(6,164)
Estimated fair value	$ 41,217		41,217		$ 54,240
Loss on the write-off of an AFS debt security			$ 5,000

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Amount of writeoff of 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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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Topic 320
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Amortized cost of 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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