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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
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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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