CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (unaudited) [Abstract]
Net earnings (loss) available to common stockholders	$ 746	$ (100,696)
Other comprehensive income:
Currency translation adjustment, net of taxes of ($32) in 2017 and $0 in 2016	1,910	1,029
Unrealized holding gains on marketable securities arising during the period, net of taxes of $178 in 2017 and $27 in 2016	(279)	43
Change in unfunded SERP liability, net of taxes of ($32) in 2017 and $72 in 2016	62	434
Other comprehensive income	1,693	1,506
Comprehensive income (loss)	$ 2,439	$ (99,190)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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