Components of Change in Other Assets and Liabilities Net (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Supplemental Cash Flow Elements [Abstract]
Other current and noncurrent assets	$ (4,579)	$ 3,998
Accrued salaries, benefits and payroll taxes	(11,829)	27,911
Accrued insurance and other taxes	12,152	10,510
Accrued income taxes	13,143	7,096
Accrued pension, postretirement and postemployment benefits	(24,232)	(2,136)
Other current and noncurrent liabilities	4,770	(742)
Change in other assets and liabilities	$ (10,575)	$ 46,637