Business combination equity interest exchange ratio.

No definition available.

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- Definition

Amount of premium associated with deposit liabilities included in branch divestitures.

+ References

No definition available.

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- Definition

Amount of deposits expected to be included in branch divestitures.

+ References

No definition available.

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- Definition

Net gain realized from the divestitures of certain branch offices, which may include deposit and loan premiums, goodwill allocations, and certain other fees associated with the transactions.

+ References

No definition available.

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- Definition

Number of locations to be closed.

+ References

No definition available.

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- Definition

Number of banking centers consolidated into existing branch locations.

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-Paragraph 2
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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
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- Definition

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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- Definition

The face amount of loans that will be sold to other entities.

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- Definition

Represents the number of stores.

+ References

No definition available.

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Acquisition and Divestiture Activity - Additional Information (Detail) $ in Thousands, shares in Millions				3 Months Ended	12 Months Ended		14 Months Ended
	Jan. 21, 2020 Branch	Nov. 01, 2018 USD ($) Branch shares	Oct. 26, 2018 USD ($) Branch	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Branch	Dec. 31, 2018 USD ($) Branch	Dec. 31, 2019 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Net pre-tax gain						$ 13,989
Goodwill allocation				$ 1,036,258	$ 1,036,994	$ 1,036,258	$ 1,036,994	$ 828,051	$ 655,018
Number of banking centers consolidated \| Branch					1	10
Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	31
Marine Credit Union of La Crosse, Wisconsin [Member]
Business Acquisition [Line Items]
Number of branches \| Branch			10
Deposits			$ 230,600
Purchasers assumed loans			$ 0
Net pre-tax gain				14,000
Deposit premium				15,000
Goodwill allocation				600		$ 600
Other transaction expense related to divestitures				$ 400
Minnesota [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	4
Wisconsin [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	10
Indiana [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	10
Michigan [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	5
Kentucky [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of banking centers to be closed \| Branch	2
KleinBank [Member] \| Minnesota [Member]
Business Acquisition [Line Items]
Stock merger acquisition ratio		100.00%
Number of branches \| Branch		18
Portion of share received by merged entity		7.92
Total fair value of consideration paid		$ 406,500
Issuance of common stock shares for acquisitions of business \| shares		22.8
Value of issuance common stock shares		$ 406,500
Transaction and integration costs associated with the acquisition							$ 20,300
Goodwill allocation		208,771
KleinBank [Member] \| Minnesota [Member] \| Core Deposit [Member]
Business Acquisition [Line Items]
Estimated fair value of intangible assets acquired		$ 39,000
Estimated useful life of intangible assets		12 years