Fair Value - Fair Value Measurements of Other Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Cash and due from banks	$ 252,138	$ 214,894
Interest-bearing deposits in other banks	229,474	84,327
Securities held-to-maturity	19,825
FHLB and FRB stock	154,357	115,409
Loans	13,745,069	12,732,308
Investment in BOLI	298,827	296,351
Liabilities
Deposits	14,098,950	13,251,278
Borrowed funds	2,648,210	1,658,758
Senior and subordinated debt	234,153	233,948
Carrying Amount \| Level 1
Assets
Cash and due from banks	252,138	214,894
Carrying Amount \| Level 2
Assets
Interest-bearing deposits in other banks	229,474	84,327
Securities held-to-maturity	19,825	21,997
FHLB and FRB stock	154,357	115,409
Liabilities
Deposits	14,098,950	13,251,278
Borrowed funds	2,648,210	1,658,758
Senior and subordinated debt	234,153	233,948
Accrued interest payable	8,869	10,502
Carrying Amount \| Level 3
Assets
Loans	13,745,659	12,733,200
Investment in BOLI	298,827	296,351
Accrued interest receivable	61,333	59,716
Fair Value \| Level 1
Assets
Cash and due from banks	252,138	214,894
Fair Value \| Level 2
Assets
Interest-bearing deposits in other banks	229,474	84,327
Securities held-to-maturity	19,842	21,234
FHLB and FRB stock	154,357	115,409
Liabilities
Deposits	14,104,641	13,247,871
Borrowed funds	2,648,210	1,658,758
Senior and subordinated debt	261,970	277,203
Accrued interest payable	8,869	10,502
Fair Value \| Level 3
Assets
Loans	13,749,883	12,535,848
Investment in BOLI	298,827	296,351
Accrued interest receivable	$ 61,333	$ 59,716

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums over and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans and leases covered under loss sharing agreements.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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