Financial Ratios under Senior Credit Facility (Detail)	3 Months Ended
	Jun. 30, 2013	Mar. 31, 2013
Required [Member]
Financial Ratios Under Senior Credit Facility [Line Items]
Leverage Ratio (maximum)	3.5	3.5
Interest Coverage Ratio (minimum)	2.55	2.55
Actual [Member]
Financial Ratios Under Senior Credit Facility [Line Items]
Leverage Ratio (maximum)	1.79	1.98
Interest Coverage Ratio (minimum)	8.74	8.39