Derivative Financial Instruments - Notional amounts and fair values of derivative financial instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative Financial Instruments
Notional Amount	$ 386,626	$ 688,786
Asset (Liability) Fair Value	1,728	5,159
Interest rate lock commitments
Derivative Financial Instruments
Notional Amount	217,546	428,828
Asset (Liability) Fair Value	1,352	6,832
Interest rate lock commitments \| Other Assets
Derivative Financial Instruments
Notional Amount	159,507	406,422
Asset (Liability) Fair Value	1,712	6,932
Interest rate lock commitments \| Other Liabilities
Derivative Financial Instruments
Notional Amount	58,039	22,406
Asset (Liability) Fair Value	(360)	(100)
Forward Commitments
Derivative Financial Instruments
Notional Amount	97,500	218,000
Asset (Liability) Fair Value	425	(1,572)
Forward Commitments \| Other Assets
Derivative Financial Instruments
Notional Amount	86,000
Asset (Liability) Fair Value	447
Forward Commitments \| Other Liabilities
Derivative Financial Instruments
Notional Amount	11,500	218,000
Asset (Liability) Fair Value	(22)	(1,572)
Customer derivatives - interest rate swaps
Derivative Financial Instruments
Notional Amount	71,580	41,958
Asset (Liability) Fair Value	(49)	(101)
Customer derivatives - interest rate swaps \| Other Assets
Derivative Financial Instruments
Notional Amount	35,790	20,979
Asset (Liability) Fair Value	1,052	1,118
Customer derivatives - interest rate swaps \| Other Liabilities
Derivative Financial Instruments
Notional Amount	35,790	20,979
Asset (Liability) Fair Value	$ (1,101)	$ (1,219)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

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.

+ References

No definition available.

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