Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 895,224	$ 607,665
Securities available for sale, Unrealized Gains	13,728	20,462
Securities available for sale, Unrealized Losses	6,107	68
Securities available for sale	902,845	628,059
Securities held to maturity, Amortized Cost	218,864	271,973
Securities held to maturity, Unrealized Gains	7,180	10,062
Securities held to maturity, fair value	226,044	282,035
Allowance for credit losses, Amortized Cost	(6)	(7)
Held-to-maturity securities, net , Amortized Cost	218,858	271,966
U.S. Government Agency And Government Sponsored Enterprises [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	6,249	6,239
Securities available for sale, Unrealized Gains	314	396
Securities available for sale	6,563	6,635
State And Political Subdivisions [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Amortized Cost	113,437	144,506
Securities held to maturity, Unrealized Gains	3,383	4,478
Securities held to maturity, fair value	116,820	148,984
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	20,362	3,047
Securities available for sale, Unrealized Gains	69	97
Securities available for sale, Unrealized Losses	79
Securities available for sale	20,352	3,144
Securities held to maturity, Amortized Cost	24,099	29,988
Securities held to maturity, Unrealized Gains	808	1,075
Securities held to maturity, fair value	24,907	31,063
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	6,747
Securities available for sale, Unrealized Losses	47
Securities available for sale	6,700
Securities held to maturity, Amortized Cost	28,847	35,897
Securities held to maturity, Unrealized Gains	1,092	1,581
Securities held to maturity, fair value	29,939	37,478
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Amortized Cost	6,563	7,864
Securities held to maturity, Unrealized Gains	205	265
Securities held to maturity, fair value	6,768	8,129
Collateralized Mortgage Obligations [Member] \| Privately Issued [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Unrealized Gains	424	435
Securities available for sale	424	435
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	888,975	601,426
Securities available for sale, Unrealized Gains	13,414	20,066
Securities available for sale, Unrealized Losses	6,107	68
Securities available for sale	896,282	621,424
Securities held to maturity, Amortized Cost	105,427	127,467
Securities held to maturity, Unrealized Gains	3,797	5,584
Securities held to maturity, fair value	109,224	133,051
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	514,661	350,627
Securities available for sale, Unrealized Gains	10,821	15,549
Securities available for sale, Unrealized Losses	2,400	44
Securities available for sale	523,082	366,132
Securities held to maturity, Amortized Cost	9,649	10,776
Securities held to maturity, Unrealized Gains	509	703
Securities held to maturity, fair value	10,158	11,479
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	301,495	225,645
Securities available for sale, Unrealized Gains	1,563	3,155
Securities available for sale, Unrealized Losses	3,357	24
Securities available for sale	299,701	228,776
Securities held to maturity, Amortized Cost	5,099	5,858
Securities held to maturity, Unrealized Gains	212	382
Securities held to maturity, fair value	5,311	6,240
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	45,710	22,107
Securities available for sale, Unrealized Gains	537	830
Securities available for sale, Unrealized Losses	224
Securities available for sale	46,023	22,937
Securities held to maturity, Amortized Cost	31,170	37,084
Securities held to maturity, Unrealized Gains	971	1,578
Securities held to maturity, fair value	$ 32,141	$ 38,662

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Debt securities available for sale and held to maturity securities.

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Held-to-maturity securities, net.

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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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