CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income	$ 11,584	$ 10,798
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation and amortization	22,494	14,554
Provision for doubtful accounts	854	71
Amortization and write off of debt discount and debt issuance costs	112	118
Stock-based compensation	1,666	1,728
Loss on disposition of long-lived assets	1,111
Loss on deconsolidation of subsidiary	529
Other non-cash activity	375
Changes in operating assets and liabilities, excluding the effects of acquisitions:
Accounts receivable	(5,860)	(9,794)
Materials and supplies, prepayments, and other current assets	(1,789)	(1,425)
Prepaid income taxes	995
Accounts payable and accrued liabilities, advance payments and deposits and other current liabilities	(14,465)	1,652
Accrued taxes	4,341	4,363
Other assets	2,033	(2,022)
Other liabilities	8,109	8,286
Net cash provided by operating activities	32,089	28,329
Cash flows from investing activities:
Capital expenditures	(45,702)	(16,445)
Purchase of marketable securities		(2,000)
Divestiture of businesses, net of transferred cash $2.1 million	22,597
Sale of short-term investments	484
Change in restricted cash	1,769	653
Net cash used in investing activities	(20,852)	(17,792)
Cash flows from financing activities:
Dividends paid on common stock	(5,487)	(5,145)
Distribution to non-controlling stockholders	(2,828)	(3,036)
Proceeds from stock option exercises		165
Principal repayments of term loan	(4,442)	(1,535)
Purchase of common stock	(2,121)	(1,929)
Repurchases of non-controlling interests	(819)
Investments made by minority shareholders in consolidated affiliates	69
Net cash used in financing activities	(15,628)	(11,480)
Effect of foreign currency exchange rates on cash and cash equivalents	207
Net change in cash and cash equivalents	(4,184)	(943)
Cash and cash equivalents, beginning of period	269,721	392,045
Cash and cash equivalents, end of period	$ 265,537	$ 391,102