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Derivatives and Balance Sheet Offsetting (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative [Line Items]
Secured Borrowings, Gross Including Not Subject to Master Netting Arrangement	$ 29,252,000
Secured Borrowings, Gross, Difference, Amount	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	29,252,000
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	29,252,000
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	475,600,000		$ 428,600,000
Gain (Loss) on Derivative Instruments, Net, Pretax	0	$ 0
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of asset derivative instruments	49,775,000		19,144,000
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Contracts [Member]
Derivative [Line Items]
Fair value of liability derivative instruments	49,777,000		19,145,000
Designated as Hedging Instrument [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Derivative, Notional Amount	500,000,000.0
Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Fair value of asset derivative instruments	37,209,000		14,727,000
Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest rate collar [Domain]
Derivative [Line Items]
Fair value of liability derivative instruments	$ 0		$ 0