Remaining Borrowing Availability and Base Rate or London Interbank Offered Rate (LIBOR) (Detail)	9 Months Ended
	Sep. 30, 2011
Greater than $350
Debt Instrument [Line Items]
Base Rate	1.50%
LIBOR Rate	2.50%
Greater than $150 but less than or equal to $350
Debt Instrument [Line Items]
Base Rate	1.75%
LIBOR Rate	2.75%
$150 or less
Debt Instrument [Line Items]
Base Rate	2.00%
LIBOR Rate	3.00%