Loans and Allowance - Changes in Allowance for Loan Losses by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 195,397	$ 130,648
Provision for credit losses - loans	0	0
Recoveries on loans	1,052	694
Loans charged off	(465)	(4,315)
Ending balance	195,984	201,082
Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		74,055
Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		204,703
Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		130,648
Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	69,935	47,115
Provision for credit losses - loans	7,571	(932)
Recoveries on loans	139	188
Loans charged off	(8)	(673)
Ending balance	77,637	65,722
Commercial \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		20,024
Commercial \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		67,139
Commercial \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		47,115
Commercial \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	60,665	40,786
Provision for credit losses - loans	(8,250)	(1,701)
Recoveries on loans	707	164
Loans charged off	(122)	(3,313)
Ending balance	53,000	70,861
Commercial Real Estate \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		34,925
Commercial Real Estate \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		75,711
Commercial Real Estate \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		51,070
Commercial Real Estate \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(10,284)
Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	20,206	10,284
Provision for credit losses - loans	554	1,095
Recoveries on loans	0	0
Loans charged off	0	(2)
Ending balance	20,760	20,182
Construction \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		8,805
Construction \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		19,089
Construction \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Construction \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		10,284
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Provision for credit losses - loans		0
Recoveries on loans		0
Loans charged off		0
Ending balance		0
Consumer \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Consumer \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Consumer \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		9,648
Consumer \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(9,648)
Residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Provision for credit losses - loans		0
Recoveries on loans		0
Loans charged off		0
Ending balance		0
Residential \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Residential \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Residential \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		22,815
Residential \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(22,815)
Consumer & Residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	44,591	32,463
Provision for credit losses - loans	125	1,538
Recoveries on loans	206	342
Loans charged off	(335)	(327)
Ending balance	$ 44,587	44,317
Consumer & Residential \| Impact of adopting ASC 326
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		10,301
Consumer & Residential \| Adjusted balance
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		42,764
Consumer & Residential \| Previously reported
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		0
Consumer & Residential \| Credit risk reclassifications
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		$ 32,463

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

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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