Aggregate tax attribute reduction in cancellation of indebtedness.

No definition available.

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Annual limitation of company's ownership change.

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- Definition

Cancellation of indebtedness attribute reduction in the tax basis of stock of foreign subsidiaries.

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No definition available.

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- Definition

Cancellation of indebtedness impacted in net operating losses and depreciable assets.

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No definition available.

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- Definition

Cancellation of indebtedness income.

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- Definition

Deferred tax recognized on remaining of excess cancellation of indebtedness income.

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No definition available.

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- Definition

Excess cancellation of indebtedness income attributed subsidiaries.

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No definition available.

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- Definition

Global intangible low taxed income recognized.

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No definition available.

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Income Tax [Line Items]

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No definition available.

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- Definition

Net operating loss carry forwards expiration period.

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No definition available.

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Tax credit carryforward prior to ownership change date expiration.

+ References

No definition available.

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Tax cuts and jobs act of 2017 incomplete accounting provisional reduction in net deferred tax asset.

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No definition available.

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Taxable lncome limitation with indefinite carryover percentage.

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No definition available.

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- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign 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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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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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 undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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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 ($)	1 Months Ended	4 Months Ended	5 Months Ended	12 Months Ended
	Jul. 31, 2017	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 15, 2018
Income Tax [Line Items]
Federal statutory tax rate					21.00%	35.00%
Net deferred liabilities							$ 1,000,000.0
Cancellation of indebtedness (COD) income	$ 853,000,000.0
Total amount of reduction of tax attributes	718,000,000.0
Net operating losses and depreciable assets	358,000,000.0
Attribute reduction in stock of foreign subsidiaries	330,000,000.0
Excess COD income attributed to subsidiaries	122,000,000.0
Deferred tax recognized on excess COD income	14,000,000.0
Annual limitation of company's ownership change				$ 15,000,000.0
Valuation allowance				103,496,000	$ 106,447,000
Undistributed earnings of foreign subsidiaries				178,200,000
Income tax penalties and interest				24,800,000	21,600,000
Unrecognized tax benefits, period increase (decrease)				(22,900,000)
Unrecognized tax benefits that would affect the effective tax rate if recognized				48,600,000	43,800,000
Reduction in net deferred tax asset						$ 15,100,000
Valuation allowance – deferred tax assets		$ 69,278,000	$ (28,387,000)	15,707,000	38,778,000	$ 27,300,000
Global intangible low taxed income recognized				0	0
Scenario Plan
Income Tax [Line Items]
Federal statutory tax rate						21.00%
GulfMark
Income Tax [Line Items]
Annual limitation of company's ownership change				$ 7,000,000.0
Tax credit carryforward prior to ownership change date expiration				2032
Federal NOL
Income Tax [Line Items]
Net operating loss carryforwards				$ 300,000,000.0	218,100,000
Taxable income limitation with indefinite carryover				80.00%
Federal NOL \| IRC Section 382 Limitation
Income Tax [Line Items]
Net operating loss carryforwards				$ 145,900,000	$ 137,900,000
Foreign NOL
Income Tax [Line Items]
Net operating loss carryforwards				132,000,000.0
Tax credit				$ 500,000
Net operating loss carry forwards expiration period				2025
Tax credit				$ 387,000,000
Domestic Subsidiaries
Income Tax [Line Items]
Excess COD income attributed to subsidiaries	136,000,000.0
Deferred tax recognized on excess COD income	$ 0