The net amount of net tangible assets acquired at the acquisition date.

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Amount of other real estate owned acquired at the acquisition date.

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Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Bank Owned Life Insurance

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Business combination recognized identifiable assets acquired and liabilities assumed deposits.

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Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Federal Reserve Bank And Federal Home Loan Bank Stock

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Business combination recognized identifiable assets acquired and liabilities assumed loan servicing rights.

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Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Securities Sold Under Agreements to Repurchase

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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.

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Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. 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.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount, after allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date, classified as current.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisition and Divestiture Activity - Summary of Fair Values of Acquired Assets, Liabilities Assumed and Resulting Goodwill (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Nov. 01, 2018	Mar. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill	$ 1,036,258	$ 1,036,258		$ 828,804	$ 828,051
KleinBank [Member] \| Minnesota [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			$ 60,759
Investment securities			697,951
FHLB/Federal Reserve Bank stock			2,637
Loans held for sale			3,371
Loans			1,049,073
Premises and equipment			33,391
Accrued interest receivable			7,896
Company-owned life insurance			36,380
Net deferred tax assets			6,500
Other real estate owned			954
Other assets			10,299
Deposits			(1,713,086)
Securities sold under agreements to repurchase			(19,481)
Accrued expenses and other liabilities			(17,506)
Net tangible assets acquired			159,138
Definite-lived intangible assets acquired			39,017
Loan servicing rights			285
Goodwill			208,034
Total consideration			$ 406,474