Changes in Accumulated Other Comprehensive Loss Net of Tax (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period, Pension and Postretirement Benefit Plans	$ (108,189)	$ (84,204)
Other comprehensive loss before reclassifications, net of tax, Pension and Postretirement Benefit Plans
Amounts reclassified from accumulated other comprehensive loss, net of tax, Pension and Postretirement Benefit Plans	1,893	1,548
Other comprehensive earnings, net of tax, Pension and Postretirement Benefit Plans	1,893	1,548
Balance at end of period, Pension and Postretirement Benefit Plans	(106,296)	(82,656)
Balance at beginning of period, Foreign Currency	6,157	5,076
Other comprehensive loss before reclassifications, net of tax, Foreign Currency	(834)	199
Amounts reclassified from accumulated other comprehensive loss, net of tax, Foreign Currency
Other comprehensive earnings, net of tax, Foreign Currency	(834)	199
Balance at end of period, Foreign Currency	5,323	5,275
Balance at beginning of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	(4,137)	(4,762)
Other comprehensive loss before reclassifications, net of tax, Unamortized Value of Terminated Forward Starting Interest Rate Swap
Amounts reclassified from accumulated other comprehensive loss, net of tax, Unamortized Value of Terminated Forward Starting Interest Rate Swap	162	152
Other comprehensive earnings, net of tax, Unamortized Value of Terminated Forward Starting Interest Rate Swap	162	152
Balance at end of period, Unamortized Value of Terminated Forward Starting Interest Rate Swap	(3,975)	(4,610)
Balance at beginning of period, Accumulated Other Comprehensive Loss	(106,169)	(83,890)
Other comprehensive loss before reclassifications, net of tax, Accumulated Other Comprehensive Loss	(834)	199
Amounts reclassified from accumulated other comprehensive loss, net of tax,Accumulated Other Comprehensive Loss	2,055	1,700
Other comprehensive earnings, net of tax, Accumulated Other Comprehensive Loss	1,221	1,899
Balance at end of period, Accumulated Other Comprehensive Loss	$ (104,948)	$ (81,991)