Consolidated Statements of Cash Flows Supplemental Disclosures Statement - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash payments:
Payments to redeem long-term debt prior to contractual maturity	$ 0	$ 0	$ 27,735
Interest	29,917	32,371	38,978
Income taxes	3,170	1,878	622
Non-cash Transactions
Capital lease	0	525	0
Business combination, value of equity issued	2,972	3,500	0
Common stock, joint venture acquisition	513	0	0
Proceeds from sale of minority interest in subsidiary		50
NAME
Non-cash Transactions
Business combination, value of equity issued	0	0	4,950
Proceeds from sale of minority interest in subsidiary	$ 0	$ 0	$ 225