Amount of investment in debt security measured at amortized cost, before allowance for credit losses.

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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).

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Amount, before tax, of unrealized loss 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).

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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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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Securities held-to-maturity, amortized cost	$ 58,734
Securities held-to-maturity, amortized cost	57,890		$ 57,832
Securities held-to-maturity, fair value	62,446		63,529
Securities held-to-maturity, gross Unrecognized gains	3,712		4,790
Securities held-to-maturity, gross Unrecognized losses	0
Securities held-to-maturity, allowance for credit losses	(844)	$ (915)	(907)	$ (402)	$ (402)	$ (340)
Securities available for sale, amortized cost, total other securities	820,738		646,112
Securities available for sale, fair value	821,445		647,974
Securities available for sale, gross unrealized gains	5,947		9,628
Securities available for sale, gross unrealized losses	5,240		7,766
Other Securities [Member]
Securities available for sale, amortized cost, total other securities	1,495		1,295
Securities available for sale, fair value	1,495		1,295
Securities available for sale, gross unrealized gains	0		0
Securities available for sale, gross unrealized losses	0		0
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	6,206		6,452
Securities available for sale, fair value	6,218		6,453
Securities available for sale, gross unrealized gains	15		2
Securities available for sale, gross unrealized losses	3		1
Corporate Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	117,420		130,000
Securities available for sale, fair value	117,602		123,865
Securities available for sale, gross unrealized gains	461		131
Securities available for sale, gross unrealized losses	279		6,266
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	50,830		50,825
Securities held-to-maturity, fair value	53,598		54,538
Securities held-to-maturity, gross Unrecognized gains	2,768		3,713
Securities held-to-maturity, gross Unrecognized losses	0
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	12,585		12,703
Securities available for sale, fair value	12,585		12,703
Securities available for sale, gross unrealized gains	0		0
Securities available for sale, gross unrealized losses	0		0
Collateralized Debt Obligations [Member]
Securities available for sale, amortized cost, total other securities	87,148		100,561
Securities available for sale, fair value	86,884		99,198
Securities available for sale, gross unrealized gains	18		0
Securities available for sale, gross unrealized losses	282		1,363
Other Debt Obligations [Member]
Securities held-to-maturity, amortized cost	50,830		50,825
Securities held-to-maturity, amortized cost	49,986		49,918
Securities held-to-maturity, fair value	53,598		54,538
Securities held-to-maturity, gross Unrecognized gains	2,768		3,713
Securities held-to-maturity, gross Unrecognized losses	0
Securities held-to-maturity, allowance for credit losses	(844)		(907)
Securities available for sale, fair value	224,784		243,514
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,904		7,914
Securities held-to-maturity, amortized cost	7,904		7,914
Securities held-to-maturity, fair value	8,848		8,991
Securities held-to-maturity, gross Unrecognized gains	944		1,077
Securities held-to-maturity, gross Unrecognized losses	0
Securities available for sale, amortized cost, total other securities	595,884		395,101
Securities available for sale, fair value	596,661		404,460
Securities available for sale, gross unrealized gains	5,453		9,495
Securities available for sale, gross unrealized losses	4,676		136
REMIC and CMO [Member]
Securities available for sale, amortized cost, total other securities	222,748		175,142
Securities available for sale, fair value	224,065		180,877
Securities available for sale, gross unrealized gains	3,042		5,735
Securities available for sale, gross unrealized losses	1,725		0
GNMA [Member]
Securities available for sale, amortized cost, total other securities	12,033		13,009
Securities available for sale, fair value	11,802		13,053
Securities available for sale, gross unrealized gains	39		66
Securities available for sale, gross unrealized losses	270		22
FNMA [Member]
Securities held-to-maturity, amortized cost	7,904		7,914
Securities held-to-maturity, fair value	8,848		8,991
Securities held-to-maturity, gross Unrecognized gains	944		1,077
Securities held-to-maturity, gross Unrecognized losses	0
Securities available for sale, amortized cost, total other securities	205,159		143,154
Securities available for sale, fair value	205,782		146,169
Securities available for sale, gross unrealized gains	1,783		3,046
Securities available for sale, gross unrealized losses	1,160		31
FHLMC [Member]
Securities available for sale, amortized cost, total other securities	155,944		63,796
Securities available for sale, fair value	155,012		64,361
Securities available for sale, gross unrealized gains	589		648
Securities available for sale, gross unrealized losses	1,521		83
Available for Sale Securities Excluding Mortgage Backed Securities [Member]
Securities available for sale, amortized cost, total other securities	224,854		251,011
Securities available for sale, fair value	224,784		243,514
Securities available for sale, gross unrealized gains	494		133
Securities available for sale, gross unrealized losses	$ 564		$ 7,630