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Derivatives and Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 3,200
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	15,322	$ 0
Gain (Loss) on Derivative Instruments, Net, Pretax	(1)	8	$ 16
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	64,437
Secured Borrowings, Gross, Difference, Amount	0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	595	0
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]
Derivative Asset, Fair Value, Gross Asset	14,727	0
Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	428,600	366,700
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	19,144	7,033
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	19,145	$ 7,033
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	64,437
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] \| Maturity Overnight [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	64,437
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] \| Maturity Less than 30 Days [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	0
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] \| Maturity 30 to 90 Days [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	0
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member] \| Maturity Greater than 90 Days [Member]
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	$ 0