Debt - Summary of Debt (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	0 Months Ended	12 Months Ended
	Sep. 10, 2012	Dec. 31, 2013	Dec. 31, 2013 Property under Capital Leases [Member]	Dec. 31, 2012 Property under Capital Leases [Member]
Debt Instrument [Line Items]
Capital lease obligations fixed interest rate		13.00%
Property, plant and equipment, net			$ 47	$ 309
Lease expiration date		2014-03
Future minimum capital lease payment		117
Future lease payment interest		2
Debt issuance date		Sep. 10, 2012
Senior notes principal amount	600,000
Senior notes maturity		Sep. 15, 2022
Senior notes effective interest rate		3.97%
Senior notes proceeds	593,900
Frequency of Senior Notes payment		Semi-annually in arrears on March 15 and September 15
Commencement date of Senior Notes payment		Mar. 15, 2013
Repurchase agreement maximum loan borrowing capacity		$ 25,000
Expiration date of Repurchase Agreement		Jul. 30, 2014