Supplemental Cash Flow Disclosures - Non-cash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Cash paid during the period for:
Interest			$ 25,780	$ 14,995
Income Taxes Paid, Net			18,750	17,394
Non-cash investing and financing activities:
Loans Transferred to Other Real Estate Owned and Repossessions			3,346	2,154
Fair value of loans transferred from held to maturity to held for sale			29,765	13,292
Gross (decrease) increase in market value adjustment to securities available for sale			(16,806)	5,240
Gross increase (decrease) in market value adjustment to derivatives			175	(538)
Unsettled Bank Owned Life Insurance Proceeds			0	897
Other operating expenses	$ 6,645	$ 5,934	17,662	17,212
Stock Issued During Period, Value, Treasury Stock Reissued			2,257	2,258
Noncash or Part Noncash Acquisition, Value of Assets Acquired			$ 21,834	$ 36,926

Cash paid for interest and income taxes during the period.

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Gross increase in market value adjustment to securities available for sale.

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Gross Increase in Market Value Adjustment to Derivatives

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Loans Transferred to Other Real Estate Owned and Repossessions

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Unsettled Bank Owned Life Insurance Proceeds

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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The value of an asset or business acquired in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Amount of noninterest expense classified as other.

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The fair value of stock issued in noncash financing activities.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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