Investment Securities (Investments Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	$ 14	$ 193,800
Securities available for sale, Less than 12 months, Unrealized Losses	0	17,922
Securities available for sale, 12 months or longer, Fair Value	853,876	760,210
Securities available for sale, 12 months or longer, Unrealized Losses	207,291	155,102
Securities available for sale, Fair Value, Total	853,890	954,010
Securities available for sale, Unrealized Losses, Total	207,291	173,024
Total AFS debt securities with unrealized losses, Less than 12 months, Fair Value	14	193,800
Total AFS debt securities with unrealized losses, Less than 12 months, Unrealized Losses	0	17,922
Total AFS debt securities with unrealized losses, 12 months or longer, Fair Value	853,876	760,210
Total AFS debt securities with unrealized losses, 12 months or longer, Unrealized Losses	207,291	155,102
Total AFS debt securities with unrealized losses, Fair Value	853,890	954,010
Total AFS debt securities with unrealized losses, Unrealized Losses	207,291	173,024
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, Less than 12 months, Fair Value	0	0
Securities available for sale, Less than 12 months, Unrealized Losses	0	0
Securities available for sale, 12 months or longer, Fair Value	20,909	21,115
Securities available for sale, 12 months or longer, Unrealized Losses	3,626	3,420
Securities available for sale, Fair Value, Total	20,909	21,115
Securities available for sale, Unrealized Losses, Total	3,626	3,420
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, Less than 12 months, Fair Value	0	1,000
Securities available for sale, Less than 12 months, Unrealized Losses	0	94
Securities available for sale, 12 months or longer, Fair Value	8,446	8,572
Securities available for sale, 12 months or longer, Unrealized Losses	2,773	2,509
Securities available for sale, Fair Value, Total	8,446	9,572
Securities available for sale, Unrealized Losses, Total	2,773	2,603
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, Less than 12 months, Fair Value	0	0
Securities available for sale, Less than 12 months, Unrealized Losses	0	0
Securities available for sale, 12 months or longer, Fair Value	15,078	17,356
Securities available for sale, 12 months or longer, Unrealized Losses	5,121	4,163
Securities available for sale, Fair Value, Total	15,078	17,356
Securities available for sale, Unrealized Losses, Total	5,121	4,163
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	14	193,800
Securities available for sale, Less than 12 months, Unrealized Losses	0	17,922
Securities available for sale, 12 months or longer, Fair Value	832,967	739,095
Securities available for sale, 12 months or longer, Unrealized Losses	203,665	151,682
Securities available for sale, Fair Value, Total	832,981	932,895
Securities available for sale, Unrealized Losses, Total	203,665	169,604
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, Less than 12 months, Fair Value	14	154,006
Securities available for sale, Less than 12 months, Unrealized Losses	0	14,708
Securities available for sale, 12 months or longer, Fair Value	425,724	315,598
Securities available for sale, 12 months or longer, Unrealized Losses	88,324	61,485
Securities available for sale, Fair Value, Total	425,738	469,604
Securities available for sale, Unrealized Losses, Total	88,324	76,193
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, Less than 12 months, Fair Value	0	28,493
Securities available for sale, Less than 12 months, Unrealized Losses	0	2,199
Securities available for sale, 12 months or longer, Fair Value	300,727	313,728
Securities available for sale, 12 months or longer, Unrealized Losses	81,037	66,409
Securities available for sale, Fair Value, Total	300,727	342,221
Securities available for sale, Unrealized Losses, Total	81,037	68,608
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, Less than 12 months, Fair Value	0	10,301
Securities available for sale, Less than 12 months, Unrealized Losses	0	921
Securities available for sale, 12 months or longer, Fair Value	82,992	83,841
Securities available for sale, 12 months or longer, Unrealized Losses	26,410	17,116
Securities available for sale, Fair Value, Total	82,992	94,142
Securities available for sale, Unrealized Losses, Total	$ 26,410	$ 18,037

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