Mortgage Banking Activities - Schedule of components of residential loan fee income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Net gains on sales of residential loans held for sale	$ 22,761	$ 29,771	$ 74,604	$ 59,328
Mortgage banking fees	2,248	2,723	7,777	5,749
Residential loan fee income	21,323	31,226	76,704	61,888
Interest rate lock commitments
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Net change in	(1,288)	1,149	(6,356)	4,788
Forward Contracts
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Net change in	(1,017)	(3,717)	6,847	(11,167)
Loans Held For Sale
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Net gains on sales of residential loans held for sale			74,842	59,328
SBA loan fair value gain	$ (1,381)	$ 1,300	$ (6,168)	$ 3,190

Fees And Commissions, And Other Non-Interest Income

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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.

+ References

No definition available.

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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14172-108612

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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Subsection Instruction 3

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123605502&loc=d3e21310-158488

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-Name Accounting Standards Codification
-Topic 944
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Topic 944
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-Section 50
-Paragraph 1
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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-Topic 230
-SubTopic 10
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