Income Taxes - Reconciliation of Statutory Rate and Effective Rate (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Statutory rate	35.00%	35.00%	35.00%
State income taxes-net of federal income tax benefit	5.75%	5.75%	5.75%
Statutory federal tax rate change	21.30%	0.00%	0.00%
Noncontrolling interests	82.58%	(24.63%)	(10.61%)
Other	0.67%	0.00%	(0.72%)
Deferred tax asset valuation allowance	(145.31%)	(8.51%)	0.00%
Expiration of unused loss carryforwards	0.01%	(0.06%)	(16.92%)
Effective rate	0.00%	7.55%	12.50%

Effective Income Tax Rate Reconciliation, Expired Unused Loss Carryforward

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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
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-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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