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Derivatives and Balance Sheet Offsetting (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Derivative [Line Items] |  |  |
Gain (Loss) on Derivative Instruments, Net, Pretax | $ 0 |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 23,018 |  |
Secured Borrowings, Gross, Difference, Amount | 0 |  |
Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness | 0 | $ 0 |
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Derivative [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 23,018 |  |
Maturity Overnight [Member] | U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Derivative [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 23,018 |  |
Maturity Less than 30 Days [Member] | U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Derivative [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 0 |  |
Maturity 30 to 90 Days [Member] | U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Derivative [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 0 |  |
Maturity Greater than 90 Days [Member] | U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] |  |  |
Derivative [Line Items] |  |  |
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement | 0 |  |
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 369,800 |  | $ 366,700
Gain (Loss) on Derivative Instruments, Net, Pretax |  | $ 6 |
Not Designated as Hedging Instrument [Member] | Other Assets [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Fair value of asset derivative instruments | 8,815 |  | 7,033
Not Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Fair value of liability derivative instruments | 8,815 |  | 7,033
Designated as Hedging Instrument [Member] | Interest rate collar [Domain] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 500,000 |  |
Designated as Hedging Instrument [Member] | Other Assets [Member] | Interest rate collar [Domain] |  |  |
Derivative [Line Items] |  |  |
Fair value of asset derivative instruments | 6,268 |  | 0
Designated as Hedging Instrument [Member] | Other Liabilities [Member] | Interest rate collar [Domain] |  |  |
Derivative [Line Items] |  |  |
Fair value of liability derivative instruments | $ 0 |  | $ 0

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