Accumulated Other Comprehensive Loss - Net Change and Ending Balances for Various Components of Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (45,865)	$ (82,375)	$ (79,290)
Net Change	(22,888)	36,510	(3,085)
Ending balance	(68,753)	(45,865)	(82,375)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	277	(1,543)	(4,736)
Net Change	(4,703)	1,820	3,193
Ending balance	(4,426)	277	(1,543)
Unrecognized Components of Employee Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(47,462)	(81,783)	(75,225)
Net Change	(17,934)	34,321	(6,558)
Ending balance	(65,396)	(47,462)	(81,783)
Unrealized Holding Gains (Losses) on Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,007	633	562
Net Change	(23)	374	71
Ending balance	984	1,007	633
Realized (Gains) Losses from Settlement of Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	313	318	109
Net Change	(228)	(5)	209
Ending balance	$ 85	$ 313	$ 318