Debt - Summary of Debt (Parenthetical) (Detail)	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Senior Secured Credit Facilities [Member] | Term Loan B Three Loans Due Two Thousand Eighteen [Member]
Debt Instrument [Line Items]
Maturity year	2018	2018
Senior Secured Credit Facilities [Member] | Term Loan B Four Loans Due Two Thousand Eighteen [Member]
Debt Instrument [Line Items]
Maturity year	2018	2018
Senior Secured Notes, Due 2018 [Member]
Debt Instrument [Line Items]
Maturity year	2018	2018
Junior Lien Secured Notes, Due 2018 [Member]
Debt Instrument [Line Items]
Maturity year	2018	2018
Senior Notes, Due 2018 [Member]
Debt Instrument [Line Items]
Maturity year	2018	2018