Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net income	$ 32,487	$ 37,007
Comprehensive income, net of tax	32,487	37,007
Less: Comprehensive income attributable to noncontrolling interests, net of tax	12,490	296
Comprehensive income available to common stockholders	$ 19,997	$ 36,711

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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-SubTopic 10
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Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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