CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net earnings	$ 9,566	$ 17,297	$ 31,931	$ 42,514
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(1,693)	1,033	(2,424)	(719)
Amortization of:
Prior service benefit	(755)	(1,078)	(2,264)	(3,238)
Unrecognized loss	569	781	1,707	2,342
Unrecognized amounts	0	0	150	154
Foreign currency exchange rate changes	(22)	8	(47)	(19)
Income tax benefit related to pension and postretirement plans	68	110	143	269
Pension and postretirement plans, net of tax	(140)	(179)	(311)	(492)
Total other comprehensive income (loss), net of tax	(1,833)	854	(2,735)	(1,211)
Comprehensive income	$ 7,733	$ 18,151	$ 29,196	$ 41,303