Investment Securities (Investments Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	$ 465,673	$ 29,087
Securities available for sale, Less than 12 months, Unrealized Losses	10,442	68
Securities available for sale, 12 months or longer, Fair Value	13	8
Securities available for sale, Fair Value, Total	465,686	29,095
Securities available for sale, Unrealized Losses, Total	10,442	68
Total Securities, Less than 12 months, Fair Value	465,673	29,087
Total Securities, Less than 12 months, Unrealized Losses	10,442	68
Total Securities, 12 months or longer, Fair Value	13	8
Total Securities, Fair Value	465,686	29,095
Total Securities, Unrealized Losses	10,442	68
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	9,941
Securities available for sale, Less than 12 months, Unrealized Losses	59
Securities available for sale, Fair Value, Total	9,941
Securities available for sale, Unrealized Losses, Total	59
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	9,665
Securities available for sale, Less than 12 months, Unrealized Losses	43
Securities available for sale, 12 months or longer, Fair Value		8
Securities available for sale, Fair Value, Total	9,665	8
Securities available for sale, Unrealized Losses, Total	43
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	6,921
Securities available for sale, Less than 12 months, Unrealized Losses	22
Securities available for sale, Fair Value, Total	6,921
Securities available for sale, Unrealized Losses, Total	22
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	455,732	29,087
Securities available for sale, Less than 12 months, Unrealized Losses	10,383	68
Securities available for sale, 12 months or longer, Fair Value	13	8
Securities available for sale, Fair Value, Total	455,745	29,095
Securities available for sale, Unrealized Losses, Total	10,383	68
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	224,499	18,155
Securities available for sale, Less than 12 months, Unrealized Losses	4,432	44
Securities available for sale, 12 months or longer, Fair Value	13
Securities available for sale, Fair Value, Total	224,512	18,155
Securities available for sale, Unrealized Losses, Total	4,432	44
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	209,482	10,932
Securities available for sale, Less than 12 months, Unrealized Losses	5,760	24
Securities available for sale, Fair Value, Total	209,482	10,932
Securities available for sale, Unrealized Losses, Total	5,760	$ 24
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	5,165
Securities available for sale, Less than 12 months, Unrealized Losses	126
Securities available for sale, Fair Value, Total	5,165
Securities available for sale, Unrealized Losses, Total	$ 126

Debt securities available for sale and held to maturity securities.

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Amount of accumulated pre-tax unrealized loss on securities.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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