Fair Value - Fair Value Measurements of Other Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets
Cash and due from banks	$ 199,684	$ 211,189
Interest-bearing deposits in other banks	126,966	78,069
Securities held-to-maturity	23,277	10,176
FHLB and FRB stock	109,466	80,302
Loans	12,413,875	11,344,564
Investment in BOLI	297,118	296,733
Liabilities
Deposits	13,188,588	12,084,112
Borrowed funds	1,407,378	906,079
Senior and subordinated debt	233,538	203,808
Carrying Amount \| Level 1
Assets
Cash and due from banks	199,684	211,189
Carrying Amount \| Level 2
Assets
Interest-bearing deposits in other banks	126,966	78,069
Securities held-to-maturity	23,277	10,176
FHLB and FRB stock	109,466	80,302
Liabilities
Deposits	13,188,588	12,084,112
Borrowed funds	1,407,378	906,079
Senior and subordinated debt	233,538	203,808
Accrued interest payable	13,091	10,005
Carrying Amount \| Level 3
Assets
Loans	12,415,371	11,346,668
Investment in BOLI	297,118	296,733
Accrued interest receivable	59,765	54,847
Fair Value \| Level 1
Assets
Cash and due from banks	199,684	211,189
Fair Value \| Level 2
Assets
Interest-bearing deposits in other banks	126,966	78,069
Securities held-to-maturity	22,405	9,871
FHLB and FRB stock	109,466	80,302
Liabilities
Deposits	13,185,124	12,064,604
Borrowed funds	1,407,378	906,079
Senior and subordinated debt	272,085	211,207
Accrued interest payable	13,091	10,005
Fair Value \| Level 3
Assets
Loans	12,273,439	11,052,040
Investment in BOLI	297,118	296,733
Accrued interest receivable	$ 59,765	$ 54,847

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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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