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Derivatives and Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	$ 51,479	$ 51,479
Secured Borrowings, Gross, Difference, Amount	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	51,479	51,479
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	51,479	51,479
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	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	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	0
Not Designated as Hedging Instrument [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	533,800	533,800		$ 428,600
Gain (Loss) on Derivative Instruments, Net, Pretax	(473)	(473)	$ (2)
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of asset derivative instruments	54,424	54,424		19,144
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of liability derivative instruments	54,898	54,898		19,145
Designated as Hedging Instrument [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Derivative, Notional Amount	500,000	500,000
Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Fair value of asset derivative instruments	38,421	38,421		14,727
Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Fair value of liability derivative instruments	$ 0	$ 0		$ 0