Subsidiary Guarantors - Schedule of Consolidating Statement of Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 2,259	$ 1,240	$ (4,762)	$ (22,748)
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) resulting from changes in fair value of marketable securities	(44)	6	(75)	9
Other comprehensive income (loss), net of tax	(44)	6	(75)	9
Comprehensive income (loss)	2,215	1,246	(4,837)	(22,739)
Less: Comprehensive income (loss) attributable to noncontrolling interests	(37)	160	1,189	(3,750)
Comprehensive income (loss) attributable to common stockholders	2,252	1,086	(6,026)	(18,989)
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	2,296	1,080	(5,951)	(18,998)
Other comprehensive income (loss), net of tax:
Comprehensive income (loss)	2,296	1,080	(5,951)	(18,998)
Comprehensive income (loss) attributable to common stockholders	2,296	1,080	(5,951)	(18,998)
Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	15,287	12,079	27,707	18,048
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) resulting from changes in fair value of marketable securities	(44)	6	(75)	9
Other comprehensive income (loss), net of tax	(44)	6	(75)	9
Comprehensive income (loss)	15,243	12,085	27,632	18,057
Comprehensive income (loss) attributable to common stockholders	15,243	12,085	27,632	18,057
Non-Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(77)	326	2,424	(7,873)
Other comprehensive income (loss), net of tax:
Comprehensive income (loss)	(77)	326	2,424	(7,873)
Less: Comprehensive income (loss) attributable to noncontrolling interests	(37)	160	1,189	(3,750)
Comprehensive income (loss) attributable to common stockholders	(40)	166	1,235	(4,123)
Elimination [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(15,247)	(12,245)	(28,942)	(13,925)
Other comprehensive income (loss), net of tax:
Comprehensive income (loss)	(15,247)	(12,245)	(28,942)	(13,925)
Comprehensive income (loss) attributable to common stockholders	$ (15,247)	$ (12,245)	$ (28,942)	$ (13,925)

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

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=51831270

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

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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