Loans - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
PPP loans outstanding	$ 4,046,642,000	$ 3,856,281,000
Deferred processing fees	(9,519,000)	(9,924,000)
Loans, allowance for loan losses	47,547,000	47,766,000	$ 28,546,000	$ 26,399,000
Recorded investment in troubled debt restructurings (TDRs)	21,699,000	13,975,000
Increase of allowance for loan losses from modification	2,326,000	1,464,000	105,000
TDRs loans charged off	0	0	0
Total loans modified as Troubled Debt Restructuring (TDRs) with a subsequent default		1,759,000
Accretable discount on loans acquired	571,000	2,043,000
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
PPP loans outstanding	2,414,787,000	2,181,552,000
Loans, allowance for loan losses	33,277,000	32,009,000	$ 17,509,000	$ 13,158,000
Paycheck Protection Program CARES Act \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
PPP loans outstanding	68,401,000	256,336,000
Deferred processing fees	1,652,000	5,235,000
Loans, allowance for loan losses	$ 0	$ 0

Financing Receivable, Allowance For Credit Loss, Increase (Decrease) From Modification

No definition available.

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- Definition

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable.

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+ References

No definition available.

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Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

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- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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