Fair Value of Financial Instruments - Estimated Fair Values and Carrying Amounts of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Financial Assets
Cash and cash equivalents	$ 705,298	$ 510,267	$ 891,275	$ 548,095
Loans and loans held for sale, net of unearned income and allowance for loan losses	14,952,214		14,171,328
FDIC loss share receivables	29,224	39,878	50,452	$ 69,627
Derivative instruments	50,713	24,393
Financial Liabilities
Deposits	15,862,027	16,178,748	$ 16,119,541
Short-term borrowings	765,637	326,617
Long-term debt	687,436	340,447
Derivative instruments	53,441	18,058
Level 1
Financial Assets
Cash and cash equivalents	705,298	510,267
Investment securities	0	0
Loans and loans held for sale, net of unearned income and allowance for loan losses	0	0
FDIC loss share receivables	0	0
Derivative instruments	0	0
Financial Liabilities
Deposits	0	0
Short-term borrowings	0	0
Long-term debt	0	0
Derivative instruments	0	0
Level 2
Financial Assets
Cash and cash equivalents	0	0
Investment securities	2,872,254	2,901,247
Loans and loans held for sale, net of unearned income and allowance for loan losses	229,653	166,247
FDIC loss share receivables	0	0
Derivative instruments	61,598	30,486
Financial Liabilities
Deposits	0	0
Short-term borrowings	765,637	326,617
Long-term debt	0	0
Derivative instruments	64,907	24,939
Level 3
Financial Assets
Cash and cash equivalents	0	0
Investment securities	0	0
Loans and loans held for sale, net of unearned income and allowance for loan losses	14,845,335	14,508,502
FDIC loss share receivables	6,216	9,163
Derivative instruments	0	0
Financial Liabilities
Deposits	15,845,146	15,696,245
Short-term borrowings	0	0
Long-term debt	656,609	309,847
Derivative instruments	0	0
Carrying Amount
Financial Assets
Cash and cash equivalents	705,298	510,267
Investment securities	2,868,919	2,899,214
Loans and loans held for sale, net of unearned income and allowance for loan losses	14,804,762	14,355,297
FDIC loss share receivables	29,224	39,878
Derivative instruments	61,598	30,486
Financial Liabilities
Deposits	15,862,027	16,178,748
Short-term borrowings	765,637	326,617
Long-term debt	687,436	340,447
Derivative instruments	64,907	24,939
Fair Value
Financial Assets
Cash and cash equivalents	705,298	510,267
Investment securities	2,872,254	2,901,247
Loans and loans held for sale, net of unearned income and allowance for loan losses	15,074,988	14,674,749
FDIC loss share receivables	6,216	9,163
Derivative instruments	61,598	30,486
Financial Liabilities
Deposits	15,845,146	15,696,245
Short-term borrowings	765,637	326,617
Long-term debt	656,609	309,847
Derivative instruments	$ 64,907	$ 24,939

Loans and mortgage loans held for sale.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

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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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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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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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