Deferred tax and current tax assets, tax credit carryforwards, alternative minimum tax.

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Income taxes.

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Operating loss carry forward expiration year.

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Tax credit carryforwards reclassified to current tax assets.

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Amount of bad debt reserves for tax purposes of qualified lenders excluded in calculating deferred taxes.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to bad debt reserve for tax purposes of a qualified lender.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Taxes [Line Items]
Estimated revaluation of deferred tax assets					$ 39,300,000
Statutory rate	21.00%	35.00%	21.00%	35.00%
Unrecognized tax benefits, if recognized, would favorably affect the effective tax rate	$ 900,000		$ 900,000
Decrease in unrecognized tax benefits			300,000
Bad debt reserves, created for tax purposes	52,800,000		52,800,000
Unrecognized deferred income tax liability	13,000,000		13,000,000
Valuation allowance recorded	0		0		0
Operating loss carryforwards, federal	104,500,000		104,500,000		130,700,000
AMT credit carryforwards	22,600,000		22,600,000		25,100,000
Federal tax credits	12,050,000		12,050,000		5,516,000
Operating loss carryforwards, state	183,400,000		183,400,000		203,600,000
AMT carryforwards	2,545,000		2,545,000		25,084,000
State [Member]
Income Taxes [Line Items]
Tax credit carryforwards	700,000		700,000		$ 1,300,000
Internal Revenue Code Section One Zero Three One [Member]
Income Taxes [Line Items]
Tax credit carryforwards reclassified to current tax asset			20,100,000
AMT carryforwards	2,500,000		$ 2,500,000
Minimum [Member] \| State Net Operating Loss [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2024
Minimum [Member] \| Federal Net Operating Loss [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2028
Minimum [Member] \| Federal Tax Credits [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2025
Maximum [Member] \| State Net Operating Loss [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2033
Maximum [Member] \| Federal Net Operating Loss [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2033
Maximum [Member] \| Federal Tax Credits [Member]
Income Taxes [Line Items]
Operating loss carryforwards, expiration date			2038
AnchorBank WI [Member]
Income Taxes [Line Items]
Bad debt reserves, created for tax purposes	50,900,000		$ 50,900,000
Lafayette Savings Bank [Member]
Income Taxes [Line Items]
Bad debt reserves, created for tax purposes	$ 1,900,000		$ 1,900,000