Long-Term Debt - Additional Information - Long-term debt joint and several liability arrangements (Detail) - Secured Debt [Member]	6 Months Ended
Jun. 30, 2016 USD ($) Debt_Instruments CreditFacility
Debt Instrument [Line Items]
Number of debt instruments \| CreditFacility	2
Subsidiary of Common Parent [Member]
Debt Instrument [Line Items]
Number of debt instruments \| Debt_Instruments	1
Amount outstanding in the joint and several liability arrangement \| $	$ 0

Amount outstanding, before the effects of recovery, of obligation under the joint and several liability arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 405
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=34748398&loc=SL34748401-199205

Name:	us-gaap_ObligationWithJointAndSeveralLiabilityArrangementAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant