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Investment Securities - Schedule of Unrealized Losses and Estimated Fair Values (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | $ 1,032,863 | $ 3,755
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (22,142) | (10)
Estimated Fair Value, 12 Months or More | 0 | 0
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 | 0
Securities Continuous Unrealized Loss Position Fair Value | 1,032,863 | 3,755
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (22,142) | (10)
US States and Political Subdivisions Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 11,213 |
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (206) |
Estimated Fair Value, 12 Months or More | 0 |
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 |
Securities Continuous Unrealized Loss Position Fair Value | 11,213 |
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (206) |
ERROR in label resolution. |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 997 |
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (3) |
Estimated Fair Value, 12 Months or More | 0 |
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 |
Securities Continuous Unrealized Loss Position Fair Value | 997 |
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (3) |
Corporate Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 19,013 |
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (112) |
Estimated Fair Value, 12 Months or More | 0 |
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 |
Securities Continuous Unrealized Loss Position Fair Value | 19,013 |
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (112) |
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 658,965 | 3,755
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (14,779) | (10)
Estimated Fair Value, 12 Months or More | 0 | 0
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 | 0
Securities Continuous Unrealized Loss Position Fair Value | 658,965 | 3,755
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (14,779) | $ (10)
Mortgage - Backed Securities - Commercial [Member] | Obligations of U.S. Government [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 320,414 |
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (6,398) |
Estimated Fair Value, 12 Months or More | 0 |
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | 0 |
Securities Continuous Unrealized Loss Position Fair Value | 320,414 |
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | $ (6,398) |

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