Income Taxes - Reconciliation of Federal Statutory Rate to Effective Income Tax Rate on Continuing Operations (Detail)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal statutory rate (benefit)	35.00%	35.00%	35.00%
State, net of federal benefit	0.00%	10.00%	2.00%
Valuation allowance	(19.00%)	348.00%
Noncontrolling interests	(1.00%)	(3.00%)	0.00%
Installment sale ace adjustment	2.00%	0.00%	0.00%
Stock based compensation	0.00%	5.00%	0.00%
Charitable contributions	0.00%	0.00%	(1.00%)
Oil and gas percentage depletion	0.00%	(1.00%)	0.00%
Other	0.00%	1.00%	0.00%
Effective tax rate	17.00%	395.00%	36.00%

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

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Effective Income Tax Rate Reconciliation Oil And Natural Gas Percentage Depletion

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
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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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