Derivative Instruments and Hedging Activities - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Accumulated other comprehensive loss:
Beginning Balance	$ 461,215
Ending Balance	299,506
Gains (Losses) on Cash Flow Hedges [Member]
Accumulated other comprehensive loss:
Beginning Balance	(13,694)
Other comprehensive income before reclassifications	9,646
Amounts reclassified from accumulated other comprehensive loss to interest expense	(5,942)
Unrealized gain on derivatives, net of tax	3,704
Ending Balance	$ (9,990)

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

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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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