Derivatives and balance Sheet Offsetting - Collateral pledged table (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Offsetting [Line Items]
Repurchase agreements, amounts offset in balance sheet	$ 0	$ 0
repurchase agreements, net amount presented in statement of financial position	73,859	64,437
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities	(73,859)	(64,437)
securities sold under agreements to repurchase, amount not offset	0	0
Interest Rate Contracts
Balance Sheet Offsetting [Line Items]
Derivative Assets, Gross Amounts Offset in the Balance Sheets	0	0
Derivative Assets	46,184	19,144
Derivative, Collateral, Obligation to Return Securities	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	46,184	19,144
Derivative Liability, Gross Amounts Offset in Balance Sheets	0	0
Derivative Liabilities	46,637	19,145
Derivative, Collateral, Right to Reclaim Securities	(46,637)	(19,145)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	0
Interest rate collar
Balance Sheet Offsetting [Line Items]
Derivative Assets, Gross Amounts Offset in the Balance Sheets		0
Derivative Assets		14,727
Derivative Asset, Fair Value, Amount Not Offset Against Collateral		0
Derivative, Collateral, Obligation to Return Cash		(14,727)
Not Designated as Hedging Instrument \| Interest Rate Contracts \| Other Assets
Balance Sheet Offsetting [Line Items]
Derivative Asset, Fair Value, Gross Asset	46,184	19,144
Not Designated as Hedging Instrument \| Interest Rate Contracts \| Other Liabilities
Balance Sheet Offsetting [Line Items]
Derivative Liability, Fair Value, Gross Liability	46,637	19,145
Designated as Hedging Instrument \| Interest rate collar \| Other Assets
Balance Sheet Offsetting [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	14,727
Designated as Hedging Instrument \| Interest rate collar \| Other Liabilities
Balance Sheet Offsetting [Line Items]
Derivative Liability, Fair Value, Gross Liability	0	0
Available-for-sale Securities
Balance Sheet Offsetting [Line Items]
Assets Sold under Agreements to Repurchase, Carrying Amount	$ 73,859	$ 64,437

[Line Items] for Balance Sheet Offsetting [Table]

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