Income Taxes - Reconciliation of Federal Statutory Rate to Effective Income Tax Rate on Continuing Operations (Detail)			12 Months Ended
Dec. 22, 2017	Dec. 21, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal statutory rate (benefit)	21.00%	35.00%	35.00%	35.00%	35.00%
State, net of federal benefit			3.00%	0.00%	10.00%
Valuation allowance			(42.00%)	(19.00%)	348.00%
Tax rate change due to new tax act			40.00%	0.00%	0.00%
Noncontrolling interests			(1.00%)	(1.00%)	(3.00%)
Installment sale ace adjustment			0.00%	2.00%	0.00%
Stock based compensation			11.00%	0.00%	5.00%
Goodwill			25.00%	0.00%	0.00%
Merger costs			18.00%	0.00%	0.00%
Oil and gas percentage depletion			0.00%	0.00%	(1.00%)
Other			(1.00%)	0.00%	1.00%
Effective tax rate			88.00%	17.00%	395.00%

Effective Income Tax Rate Reconciliation, Installment Sale Ace Adjustment, Percent

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Effective Income Tax Rate Reconciliation, Merger Costs, Percent

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Effective Income Tax Rate Reconciliation Oil And Natural Gas Percentage Depletion

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Effective Income Tax Rate Reconciliation, Tax Goodwill, Percent

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Effective Income Tax Rate Reconciliation, Tax Rate Change Due to New Tax Act, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
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-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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Percentage 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 noncontrolling interest income (loss) exempt from income taxes.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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