CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income	$ 3,089	$ 16,931
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation	68,693	64,705
Amortization of acquisition intangibles	4,324	1,384
Provision for doubtful accounts	3,303	4,452
Amortization of debt discount and debt issuance costs	767	395
Stock-based compensation	5,116	4,608
Deferred income taxes	(5,939)	(6,078)
(Gain) loss on equity investments	(647)	3,360
Loss on disposition of long-lived assets	605	60
Unrealized (gain) loss on foreign currency	(81)	449
Changes in operating assets and liabilities, excluding the effects of acquisitions and dispositions:
Accounts receivable	152	(12,189)
Customer receivable	(25,684)
Materials and supplies, prepayments, and other current assets	(4,689)	(14,849)
Prepaid income taxes	66	2,038
Accounts payable and accrued liabilities, advance payments and deposits and other current liabilities	341	7,382
Accrued taxes	(2,172)	(1,418)
Other assets	429	1,057
Other liabilities	43	(696)
Net cash provided by operating activities	47,716	71,591
Cash flows from investing activities:
Capital expenditures	(62,222)	(48,792)
Reimbursable capital expenditures	(8,700)	(1,870)
Receipt of capital government grants	7,094
Divestiture of businesses, net of transferred cash of $0.9 million	18,597
Acquisition of business net of $11.9 million of cash acquired	(340,152)
Purchase of intangible assets; including deposits		(20,396)
Proceeds from strategic investments		11,969
Purchases of strategic investments	(6,399)	(2,768)
Purchase of short-term investments		(116)
Net cash used in investing activities	(391,782)	(61,973)
Cash flows from financing activities:
Dividends paid on common stock	(8,118)	(8,166)
Distributions to noncontrolling interests	(4,823)	(6,503)
Payment of debt issuance costs	(6,568)	(1,096)
Principal repayments of term loan and credit facilities	(13,826)	(2,814)
Credit facility borrowings	295,000
Purchases of common stock - stock-based compensation	(1,713)	(1,733)
Purchases of common stock - share repurchase plan	(4,836)	(6,589)
Proceeds from exercise of stock options	383
Redeemable noncontrolling interests contribution	71,533
Repurchases of noncontrolling interests	(13,139)	(8,763)
Proceeds from customer receivable credit facility	27,540
Net cash provided by (used in) financing activities of continuing operations	341,433	(35,664)
Effect of foreign currency exchange rates on cash and cash equivalents		(87)
Net change in cash, cash equivalents, and restricted cash	(2,633)	(26,133)
Total cash, cash equivalents, and restricted cash, beginning of period	104,997	162,358
Total cash, cash equivalents, and restricted cash, end of period	102,364	136,225
Noncash investing activity:
Purchases of property, plant and equipment included in accounts payable and accrued expenses	$ 17,973	$ 15,097