CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) [Abstract]
Net earnings (loss) available to common stockholders	$ 22,776	$ 6,062	$ (77,921)	$ 11,382	[1]
Other comprehensive income (loss):
Currency translation adjustment, net of taxes of $0 in the three months ended June 30, 2016, ($34) in the three months ended June 30, 2015, $0 in the six months ended June 30, 2016 and ($194) in the six months ended June 30, 2015	(4,071)	3,535	(3,043)	(6,801)
Unrealized gains on marketable securities arising during the period, net of taxes of $33 in the three months ended June 30, 2016, ($18) in the three months ended June 30, 2015, $60 in the six months ended June 30, 2016 and $15 in the six months ended June 30, 2015	54	(30)	98	25
Change in unfunded SERP liability, net of taxes of $32 in the three months ended June 30, 2016, $28 in the three months ended June 30, 2015, $104 in the six months ended June 30, 2016 and $56 in the six months ended June 30, 2015	66	64	500	128
Other comprehensive income (loss)	(3,951)	3,569	(2,445)	(6,648)
Comprehensive income (loss)	$ 18,825	$ 9,631	$ (80,366)	$ 4,734

[1] (Revised)