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Derivatives and Balance Sheet Offsetting Balance Sheet Offsetting (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Balance Sheet Offsetting [Line Items] |  |  |
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net | $ 9,700,000 |  |
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss) | 23,423,000 | $ 6,268,000 |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | 940,000 | 0 |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 29,252,000 |  |
Repurchase agreements, amounts offset in balance sheet | 0 |  | $ 0
Repurchase agreements, net amount presented in statement of financial position | 29,252,000 |  | 64,437,000
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities | (29,252,000) |  | (64,437,000)
Securities sold under agreements to repurchase, amount not offset | 0 |  | 0
Interest Rate Contracts [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Derivative Assets, Gross Amounts Offset in the Balance Sheets | 0 |  | 0
Derivative Asset | 49,775,000 |  | 19,144,000
Derivative, Collateral, Obligation to Return Cash | 0 |  | 0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | 49,775,000 |  | 19,144,000
Derivative Liability, Gross Amounts Offset in Balance Sheets | 0 |  | 0
Derivative Liability | 49,777,000 |  | 19,145,000
Derivative, Collateral, Right to Reclaim Cash | 49,777,000 |  | 19,145,000
Derivative Liability, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0
Interest rate collar [Domain] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Derivative Assets, Gross Amounts Offset in the Balance Sheets | 0 |  | 0
Derivative Asset | 37,209,000 |  | 14,727,000
Derivative, Collateral, Obligation to Return Cash | (37,209,000) |  | (14,727,000)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | 0 |  | 0
Available-for-sale Securities [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Securities Sold under Agreements to Repurchase, Gross | 29,252,000 |  | 64,437,000
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Gain (Loss) on Derivative Instruments, Net, Pretax | 0 | $ 0 |
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] | Other Assets [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Fair value of asset derivative instruments | 49,775,000 |  | 19,144,000
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] | Other Liabilities [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Fair value of liability derivative instruments | 49,777,000 |  | 19,145,000
Designated as Hedging Instrument [Member] | Interest rate collar [Domain] | Other Assets [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Fair value of asset derivative instruments | 37,209,000 |  | 14,727,000
Designated as Hedging Instrument [Member] | Interest rate collar [Domain] | Other Liabilities [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Fair value of liability derivative instruments | 0 |  | $ 0
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 29,252,000 |  |
Maturity Overnight [Member] | U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Balance Sheet Offsetting [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | $ 29,252,000 |  |

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