Loans - Loan Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 14,933,658	$ 12,840,330
Deferred loan fees included in total loans	9,691	7,972
Overdrawn demand deposits included in total loans	7,676	10,675
Interest receivable on loan portfolio	49,500	48,400
Commercial Industrial And Agricultural \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,789,556	4,481,525
Commercial Industrial And Agricultural \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	381,124	405,616
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,058,179	4,682,072
Commercial real estate \| Office, retail, and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	2,020,318	1,848,718
Commercial real estate \| Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	874,861	856,553
Commercial real estate \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	687,063	593,093
Commercial real estate \| Other commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,475,937	1,383,708
Commercial Portfolio Segment, Excluding PPP Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	10,228,859	9,569,213
PPP loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,179,403	0
Total corporate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	11,408,262	9,569,213
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,525,396	3,271,117
Consumer loans \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	892,867	851,454
Consumer loans \| 1-4 family mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	2,175,322	1,927,078
Consumer loans \| Installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 457,207	$ 492,585

Loans and Lease Receivable, Accrual of Interest

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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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- Definition

Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 10
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-Section S99
-Paragraph 1
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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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