Loans - Loans Sales (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total net gains on loan sales	$ 6,861	$ 2,936	$ 14,091	$ 6,327
Corporate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	13,888	117,779	196,501	307,352
Consumer Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	168,052	296,805	562,604	678,679
Corporate loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales	50	5,108	4,648	10,484
Less book value of loans sold	65	4,950	4,542	10,198
Total net gains on loan sales	(15)	158	106	286
Commercial and industrial \| Corporate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	10,196	95,967	178,912	277,577
Office, retail, and industrial \| Corporate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	0	20	0	1,731
Construction \| Corporate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	3,692	1,852	7,589	4,118
Other commercial real estate \| Corporate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	0	19,940	10,000	23,926
Home equity \| Consumer Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	0	0	144,967	77,411
1-4 family mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales	258,695	143,776	551,105	297,967
Less book value of loans sold	251,819	140,998	537,120	291,926
Total net gains on loan sales	6,876	2,778	13,985	6,041
1-4 family mortgages \| Consumer Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	168,052	293,500	417,637	597,963
Installment \| Consumer Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payments for loan purchases	$ 0	$ 3,305	$ 0	$ 3,305

The carrying amount of loans sold before adjustment for write-downs on loans held-for-sale.

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+ References

No definition available.

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- Definition

Amount of increase from purchase of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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-Publisher FASB
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-Topic 310
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-Section 50
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Amount of decrease from sale and reclassification to held-for-sale of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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Amount of gain (loss) on sale of financing receivable.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107425-111719

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