Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	$ 1,203,803	$ 1,226,150
Asset derivatives, Fair value	32,387	48,141
Liability derivatives, Fair value	32,005	47,971
Interest rate swap contracts
Derivative Financial Instruments
Asset derivatives, Fair value	35,034	52,872
Interest rate swap contracts \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	1,158,793	1,155,252
Asset derivatives, Fair value	31,311	46,654
Liability derivatives, Fair value	32,005	47,681
Loan commitments \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	22,010	32,588
Asset derivatives, Fair value	789	1,487
Liability derivatives, Fair value	0	0
Forward contracts - mortgage loan \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	23,000	38,310
Asset derivatives, Fair value	287	0
Liability derivatives, Fair value	$ 0	$ 290

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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