Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Name:	us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Change in cash flow hedges reclassed to earnings	$ (117)	$ (335)	$ (351)	$ (712)
Interest Expense [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Change in cash flow hedges reclassed to earnings			$ 400