Capital lease obligation period.

No definition available.

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- Definition

Lessee, Capital Lease, Remaining Lease Term

+ References

No definition available.

+ Details

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- Definition

Lessee, Capital Lease, Renewal Term

+ References

No definition available.

+ Details

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- Definition

Long-term capital lease term.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Long-term capital lease renewal option term.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of renewal options available for long-term capital lease.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of financial liabilities assumed (as defined) which have been recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
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Balance Type:	credit
Period Type:	instant

- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration

- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Other Borrowings - Additional Information (Detail) $ in Millions				6 Months Ended
	Nov. 01, 2017 USD ($)	May 01, 2016	Jan. 01, 2004 Item	Jun. 30, 2018	Aug. 31, 2014 USD ($)
Debt Instrument [Line Items]
Long-term capital lease obligation period, in years			25 years
Long-term capital lease obligation renewal period, in years			10 years
Number of renewal option for 10 years period \| Item			1
Anchor Bank (MN) [Member]
Debt Instrument [Line Items]
Remaining base term of lease	5 years
Renewal option available for lease in years	10 years
Capital lease obligation	$ 1.5
AnchorBank WI [Member]
Debt Instrument [Line Items]
Capital lease obligation period		5 years
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes					$ 175.0
Fixed rates					4.125%
Maturity Date				Aug. 15, 2024
Subordinated Debentures [Member] \| Anchor Bank (MN) [Member] \| Subordinated Fixed-To-Floating Notes [Member]
Debt Instrument [Line Items]
Fixed rates	5.75%
Maturity Date	Oct. 30, 2025
Value of subordinated fixed-to-floating notes assumed	$ 12.0
Subordinated debentures, maturity date	Oct. 29, 2020
Description of LIBOR Rate	Three-month LIBOR rate plus 435.6 basis points
LIBOR rate	4.356%
Debt instrument start date	Oct. 30, 2020