Income Taxes - Summary of Differences Between Total Income Tax Expense Statutory Federal Income Tax Rate (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2010
Income Tax Expense Benefit [Line Items]
Statutory rate applied to pre-tax (loss)	34.00%
Effective tax rate		37.59%
Puerto Rico [Member]
Income Tax Expense Benefit [Line Items]
Statutory rate applied to pre-tax (loss)	30.00%