ACCUMULATED OTHER COMPREHENSIVE INCOME LOSS ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Reclass) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Earnings before income taxes										$ 275,194	$ 246,944	$ 201,050
Provision for income taxes										(82,946)	(76,995)	(61,646)
Net earnings		$ 69,849	$ 33,884	$ 25,737	$ 15,991	$ 16,750	$ 25,033	$ 36,391	$ 35,164	145,461	113,338	$ 137,981
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax	[1]									39	(5)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax	[1]									(16,339)	(6,016)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Curtailments, before Tax										(7,461)	(377)
Earnings before income taxes										(23,761)	(6,398)
Provision for income taxes										8,928	2,232
Net earnings										$ (14,833)	$ (4,166)

[1] These items are included in the computation of net periodic pension cost. See Note 15, Pension and Other Postretirement Benefit Plans.