Amount of loan servicing rights at acquisition date.

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The amount of loans held for sale recognized as of the acquisition date.

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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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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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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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For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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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 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 long-term debt due within one year or within the normal operating cycle, if longer, assumed 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 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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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 short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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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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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Acquisition and Divestiture Activity - Schedule of Purchase Price Allocation (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Deposits	$ (10,743,253)	$ (8,400,860)
Securities sold under agreements to repurchase	(367,052)	(387,409)
Federal funds purchased	(213,003)	(291,090)
Federal Home Loan Bank advances	(1,353,092)	(1,023,491)
Goodwill	655,018	$ 584,634	$ 530,845
Tower Financial Corporation [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	56,345
Investment securities	140,567
Federal Home Loan Bank stock	2,192
Loans held for sale	474
Loans	371,054
Premises and equipment	8,516
Accrued interest receivable	2,371
Other real estate owned	473
Company-owned life insurance	21,281
Other assets	15,200
Deposits	(527,995)
Securities sold under agreements to repurchase	(18,898)
Federal Home Loan Bank advances	(5,500)
Other borrowings	(15,613)
Accrued expenses and other liabilities	(4,681)
Net tangible assets acquired	45,786
Definite-lived intangible assets acquired	8,382
Goodwill	56,203
Purchase price	110,371
Anchor BanCorp Wisconsin Inc [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	123,657
Investment securities	235,240
Federal Home Loan Bank stock	4,596
Loans held for sale	9,334
Loans	1,637,806
Premises and equipment	35,721
Accrued interest receivable	7,308
Other real estate owned	17,349
Company-owned life insurance	7,278
Other assets	126,210
Deposits	(1,852,713)
Securities sold under agreements to repurchase	(3,132)
Other borrowings	(123)
Accrued expenses and other liabilities	(36,957)
Net tangible assets acquired	311,574
Definite-lived intangible assets acquired	21,559
Loan servicing rights	15,274
Goodwill	111,347
Purchase price	459,754
United Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	16,447
Investment securities	154,885
Federal Home Loan Bank stock	2,880
Loans held for sale	1,073
Loans	632,016
Premises and equipment	7,741
Accrued interest receivable	2,614
Other real estate owned	1,676
Company-owned life insurance	14,857
Other assets	16,822
Deposits	(763,681)
Federal funds purchased	(10,420)
Federal Home Loan Bank advances	(12,515)
Accrued expenses and other liabilities	(8,337)
Net tangible assets acquired	56,058
Definite-lived intangible assets acquired	10,763
Loan servicing rights	8,983
Goodwill	81,952
Purchase price	157,756
LSB Financial Corp. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	7,589
Investment securities	63,684
Federal Home Loan Bank stock	3,185
Loans held for sale	1,035
Loans	235,377
Premises and equipment	6,492
Accrued interest receivable	1,044
Other real estate owned	30
Company-owned life insurance	7,438
Other assets	11,490
Deposits	(292,068)
Federal Home Loan Bank advances	(15,203)
Accrued expenses and other liabilities	(4,582)
Net tangible assets acquired	25,511
Definite-lived intangible assets acquired	2,618
Loan servicing rights	990
Goodwill	40,476
Purchase price	69,595
Founders Financial Corporation [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	3,978
Investment securities	75,383
Federal Home Loan Bank stock	1,810
Loans held for sale	3,473
Loans	339,569
Premises and equipment	3,604
Accrued interest receivable	1,260
Other real estate owned	674
Company-owned life insurance	8,297
Other assets	8,804
Deposits	(376,656)
Securities sold under agreements to repurchase	(12,492)
Federal Home Loan Bank advances	(26,888)
Accrued expenses and other liabilities	(1,307)
Net tangible assets acquired	29,509
Definite-lived intangible assets acquired	5,515
Loan servicing rights	664
Goodwill	56,014
Purchase price	$ 91,702