Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net loss	$ (231,808,000)	$ (19,105,000)	$ (84,850,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization expense	123,319,000	123,530,000	107,667,000
Impairment of goodwill	165,000,000	0	0
Impairment of fixed assets	33,697,000	0	0
Stock-based compensation expense	16,768,000	22,649,000	23,049,000
Amortization of debt discount and deferred financing costs	7,884,000	7,408,000	1,158,000
Deferred income tax expense (benefit)	(15,469,000)	(3,489,000)	16,342,000
Gain on disposals of assets	(4,291,000)	(6,288,000)	(700,000)
Other, net	3,079,000	1,411,000	288,000
Changes in operating assets and liabilities, net of effect from acquired businesses:
Accounts receivable	50,257,000	(16,792,000)	21,128,000
Inventories	(10,774,000)	(7,283,000)	11,339,000
Accounts payable and accrued liabilities	(6,173,000)	5,796,000	14,048,000
Income taxes payable	662,000	802,000	(4,126,000)
Other operating assets and liabilities, net	5,281,000	(5,469,000)	(9,961,000)
Net cash flows provided by operating activities	137,432,000	103,170,000	95,382,000
Cash flows from investing activities:
Capital expenditures	(56,116,000)	(88,024,000)	(35,171,000)
Proceeds from disposition of property, plant and equipment	6,046,000	3,659,000	2,134,000
Acquisitions of businesses, net of cash acquired	0	(379,676,000)	(12,859,000)
Proceeds from flood insurance claims	0	3,850,000	0
Other, net	(1,912,000)	(1,184,000)	(1,719,000)
Net cash flows used in investing activities	(51,982,000)	(461,375,000)	(47,615,000)
Cash flows from financing activities:
Revolving credit facility borrowings	246,828,000	835,467,000	206,015,000
Revolving credit facility repayments	(331,041,000)	(699,322,000)	(248,199,000)
Issuance of 1.50% convertible senior notes	0	200,000,000	0
Purchases of 1.50% convertible senior notes	(6,724,000)	0	0
Other debt and finance lease repayments, net	(500,000)	(537,000)	(517,000)
Payment of financing costs	(16,000)	(7,372,000)	(759,000)
Purchase of treasury stock	(757,000)	0	(16,283,000)
Shares added to treasury stock as a result of net share settlements due to vesting of restricted stock	(3,698,000)	(4,178,000)	(5,317,000)
Net cash flows (used in) provided by financing activities	(95,908,000)	324,058,000	(65,060,000)
Effect of exchange rate changes on cash and cash equivalents	(365,000)	4,000	1,952,000
Net change in cash and cash equivalents	(10,823,000)	(34,143,000)	(15,341,000)
Cash and cash equivalents, beginning of year	19,316,000	53,459,000	68,800,000
Cash and cash equivalents, end of year	8,493,000	19,316,000	53,459,000
Cash paid for:
Interest	9,626,000	9,864,000	4,206,000
Income taxes, net of refunds	$ (1,303,000)	$ 2,993,000	$ (174,000)