Securities - Securities Gross (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Less Than 12 Months
Fair Value	$ 180,332	$ 692,782
Unrealized Losses	(5,431)	(63,580)
More Than 12 Months
Fair Value	1,031,493	536,618
Unrealized Losses	(213,241)	(108,554)
Total
Fair Value	1,211,825	1,229,400
Unrealized Losses	(218,672)	(172,134)
U.S. Government agencies
Less Than 12 Months
Fair Value	3,684	58,462
Unrealized Losses	(160)	(4,034)
More Than 12 Months
Fair Value	85,832	38,959
Unrealized Losses	(14,664)	(7,743)
Total
Fair Value	89,516	97,421
Unrealized Losses	(14,824)	(11,777)
Mortgage Backed Securities - residential
Less Than 12 Months
Fair Value	13,339	234,488
Unrealized Losses	(452)	(19,757)
More Than 12 Months
Fair Value	543,186	379,520
Unrealized Losses	(112,277)	(71,259)
Total
Fair Value	556,525	614,008
Unrealized Losses	(112,729)	(91,016)
Mortgage Backed Securities - commercial
Less Than 12 Months
Fair Value		9,677
Unrealized Losses		(426)
More Than 12 Months
Fair Value	7,284
Unrealized Losses	(674)
Total
Fair Value	7,284	9,677
Unrealized Losses	(674)	(426)
Collateralized Mortgage Obligations
Less Than 12 Months
Fair Value	15,852	135,135
Unrealized Losses	(613)	(11,331)
More Than 12 Months
Fair Value	165,104	63,792
Unrealized Losses	(32,938)	(13,588)
Total
Fair Value	180,956	198,927
Unrealized Losses	(33,551)	(24,919)
State and municipal obligations
Less Than 12 Months
Fair Value	145,686	233,439
Unrealized Losses	(4,162)	(24,291)
More Than 12 Months
Fair Value	197,579	41,510
Unrealized Losses	(45,459)	(12,823)
Total
Fair Value	343,265	274,949
Unrealized Losses	(49,621)	(37,114)
Municipal taxable
Less Than 12 Months
Fair Value	1,771	18,637
Unrealized Losses	(44)	(3,706)
More Than 12 Months
Fair Value	30,357	12,837
Unrealized Losses	(7,203)	(3,141)
Total
Fair Value	32,128	31,474
Unrealized Losses	(7,247)	(6,847)
U.S. Treasury
Less Than 12 Months
Fair Value		2,944
Unrealized Losses		(35)
More Than 12 Months
Fair Value	2,151
Unrealized Losses	(26)
Total
Fair Value	2,151	2,944
Unrealized Losses	$ (26)	$ (35)

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