Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss		$ (237,203)	$ (32,417)	$ (63,146)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization		45,908	49,059	64,862
Loss on debt extinguishment and modification		2,224	279	0
Amortization of debt issuance costs and debt discount		8,829	7,695	7,022
Allowance for credit losses		1,612	(2,573)	11,662
Foreign currency loss		2,758	494	1,712
Deferred income taxes		(3,974)	3,795	(31,734)
(Gain) loss on asset disposal		1,161	(187)	(552)
Loss on convertible debt embedded derivative (see Note 10)		0	0	24,783
Goodwill impairment charge		191,788	0	0
Non-cash compensation cost		6,307	10,055	12,256
Other, net		(3,994)	(2,409)	(3,964)
Changes in operating assets and liabilities:
Accounts receivable		46,147	27,194	15,386
Inventory		2,702	9,551	(21)
Prepaid expenses and other current assets		(210)	494	6,933
Increase (decrease) (net of the effects of acquisitions):
Accounts payable		3,782	(5,356)	(8,994)
Other accrued liabilities		(12,798)	(8,378)	9,168
Income taxes		(2,275)	1,540	(3,514)
Net cash provided by operating activities		52,764	58,836	41,859
Cash flows from investing activities:
Capital expenditures	[1]	(19,958)	(29,035)	(27,164)
Business acquisitions, net of cash acquired		(1,013)	0	0
Proceeds from disposal of assets		2,645	934	2,580
Other		25	0	(443)
Net cash used in investing activities		(18,301)	(28,101)	(25,027)
Cash flows from financing activities:
Net payments under Credit Facility revolver		(76,638)	(82,396)	(19,690)
Borrowings under ABL Facility		44,000	0	0
Payments under ABL Facility		(35,000)	0	0
Borrowings (payments) under Credit Facility term loan, net of debt discount		(50,000)	49,745	0
Borrowings under Term Loan, net of discount		242,500	0	0
Repurchase of convertible debt		(135,501)	0	0
Contingent consideration payments		0	(428)	(1,106)
Payments for debt issuance costs		(9,113)	(1,524)	(855)
Taxes paid related to net share settlement of share-based awards		(990)	(1,911)	(1,390)
Payments for debt extinguishment and equity reacquisition costs		(2,447)	0	0
Other		(272)	(291)	0
Net cash used in financing activities		(23,461)	(36,805)	(23,041)
Effect of exchange rate changes on cash		1,409	(43)	(2,055)
Net increase (decrease) in cash and cash equivalents		12,411	(6,113)	(8,264)
Cash and cash equivalents at beginning of period		12,175	18,288	26,552
Cash and cash equivalents at end of period		24,586	12,175	18,288
Cash paid (refunded) during the year for:
Interest		23,623	22,697	24,924
Income taxes		$ (9,996)	$ (3,536)	$ 2,720

[1] Excludes accrued capital expenditures for the twelve months ended December 31, 2020, 2019 and 2018.