Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Non-hedging derivative financial instruments
Derivative Financial Instruments
Derivative, Notional Amount	$ 1,226,150	$ 1,108,391
Asset derivatives, Fair value	48,141	22,160
Liability derivatives, Fair value	47,971	22,390
Interest rate swap contracts
Derivative Financial Instruments
Asset derivatives, Fair value	52,872	22,279
Interest rate swap contracts \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Derivative, Notional Amount	1,155,252	1,074,809
Asset derivatives, Fair value	46,654	21,975
Liability derivatives, Fair value	47,681	22,352
Loan commitments \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Derivative, Notional Amount	32,588	9,950
Asset derivatives, Fair value	1,487	185
Liability derivatives, Fair value	0	0
Forward contracts - mortgage loan \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Derivative, Notional Amount	38,310	23,632
Asset derivatives, Fair value	0	0
Liability derivatives, Fair value	$ 290	$ 38

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Nominal or face amount used to calculate payment on derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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