Margin Based on Remaining Borrowing Availability (Detail) (Revolving Credit Facility [Member])	12 Months Ended
	Dec. 31, 2014
Base Rate [Member] | Greater than $350
Debt Instrument [Line Items]
Margin Rate	0.50%
Base Rate [Member] | Greater than $150 but less than or equal to $350
Debt Instrument [Line Items]
Margin Rate	0.75%
Base Rate [Member] | $150 or less
Debt Instrument [Line Items]
Margin Rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] | Greater than $350
Debt Instrument [Line Items]
Margin Rate	1.50%
London Interbank Offered Rate (LIBOR) [Member] | Greater than $150 but less than or equal to $350
Debt Instrument [Line Items]
Margin Rate	1.75%
London Interbank Offered Rate (LIBOR) [Member] | $150 or less
Debt Instrument [Line Items]
Margin Rate	2.00%