Debt - $925 Million Credit Facility - Additional Information (Detail) (USD $)	12 Months Ended						12 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2011	Apr. 18, 2013	Dec. 31, 2012	Aug. 01, 2011	Jul. 25, 2011	Dec. 31, 2012 $925 Million Credit Facility [Member]	Dec. 31, 2012 $925 Million Credit Facility [Member] Senior Secured Revolving Credit Facility [Member]	Dec. 31, 2012 $925 Million Credit Facility [Member] Senior Secured Term Loan Facility [Member]	Dec. 31, 2013 $925 Million Credit Facility [Member]	Dec. 31, 2011 $925 Million Credit Facility [Member]	Dec. 31, 2012 $925 Million Credit Facility [Member]
Debt Instrument [Line Items]
Total credit facility			$ 925,000,000	$ 925,000,000	$ 1,000,000,000	$ 1,000,000,000		$ 525,000,000	$ 400,000,000			$ 925,000,000
Accordion feature allowing potential increase to credit facility							475,000,000
Maturity Date							Aug. 01, 2015
Write-off of deferred financing costs	$ 1,845,000	$ 1,681,000								$ 1,300,000	$ 1,700,000