Long-Term Debt, Short-Term Debt, and Financing Arrangements - Financial Ratios Under Senior Credit Facility (Detail)	3 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015
Required
Debt Instrument [Line Items]
Leverage Ratio (maximum)	3.5	3.5	3.50	3.5
Interest Coverage Ratio (minimum)	2.75	2.75	2.75	2.75
Actual
Debt Instrument [Line Items]
Leverage Ratio (maximum)	1.32	1.51	1.36	1.41
Interest Coverage Ratio (minimum)	13.99	13.07	12.43	11.95