Condensed Consolidated Statement of Equity (unaudited) - 6 months ended Jun. 30, 2018 - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in-Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Company Shares Held by SERP [Member]	Retained Earnings [Member]	Non-controlling Interest [Member]	Total
Balance at Dec. 31, 2017	$ 4,614	$ 141,931	$ (24,243)	$ (1,960)	$ 565,330	$ 1,093	$ 686,765
Balance (in shares) at Dec. 31, 2017	23,070
Net income (loss)	$ 0	0	0	0	(20,407)	(145)	(20,552)
Other comprehensive loss	0	0	(6,244)	0	0	(140)	(6,384)
Change in ownership percentage of subsidiary	0	0	0	0	0	(109)	(109)
Dividends declared	0	5	0	0	(4,623)	0	(4,618)
Stock-based compensation	0	1,890	0	0	0	0	1,890
Stock issued under incentive plans	$ 5	(5)	0	0	0	0	0
Stock issued under incentive plans (in shares)	24
Withholding tax paid upon vesting of RSUs	$ 0	(432)	0	0	0	0	(432)
SERP transactions, net	0	207	0	72	0	0	279
Other	0	0	0	0	0	142	142
Balance at Jun. 30, 2018	$ 4,619	$ 143,596	$ (30,487)	$ (1,888)	$ 540,300	$ 841	$ 656,981
Balance (in shares) at Jun. 30, 2018	23,094