Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities
Net (loss) income	$ 39,421	$ 37,557
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	110,883	155,285
Amortization of debt issuance costs	801	856
Deferred income taxes	(42,346)	(25,517)
Provision for bad debt	27,709	21,945
Provision for service credits	28,268	20,752
Stock-based compensation (benefit) expense	(4,195)	9,536
Other components of net periodic pension cost	31,312	19,797
Loss on early extinguishment of debt	0	6,375
Loss on disposal/write-off of fixed assets and capitalized software	3,476	5,294
Impairment charges	19,414	5,059
Non-cash loss from remeasurement of indemnification asset	3,878	4,646
Changes in working capital items, excluding acquisitions:
Accounts receivable	15,742	51,659
Contract assets	(803)	1,885
Deferred costs	3,500	4,105
Prepaid and other assets	(7,285)	(8,822)
Accounts payable and accrued liabilities	(81,292)	(89,270)
Accrued income taxes, net	36,912	11,217
Operating lease liability	(3,998)	(7,078)
Contract liabilities	(5,911)	(3,236)
Settlement of stock option liability	(896)	(33,901)
Net cash provided by operating activities	174,590	188,144
Cash Flows from Investing Activities
Additions to fixed assets and capitalized software	(17,030)	(13,296)
Proceeds from the sale of building and fixed assets	1,546	846
Acquisition of a business, net of cash acquired	0	(147)
Net cash (used in) investing activities	(15,484)	(12,597)
Cash Flows from Financing Activities
Payments of Senior Term Loan	(72,629)	(108,262)
Payments of Senior Term Loan, related party	(32,761)	(48,738)
Proceeds from Senior Term Loan, net	0	193,625
Proceeds from Senior Term Loan, related party	0	225,000
Proceeds from ABL Facility	868,811	814,672
Payments of ABL Facility	(892,155)	(844,586)
Payments of financing obligations	(414)	(946)
Debt issuance costs	0	(774)
Purchase of treasury stock (see Note 9)	(30,626)	(437,962)
Proceeds from private placement	445	0
Proceeds from exercise of stock options	82	439
Net cash (used in) financing activities	(159,247)	(207,532)
(Decrease) in cash and cash equivalents	(141)	(31,985)
Cash and cash equivalents, beginning of period	1,912	34,169
Cash and cash equivalents, end of period	1,771	2,184
Supplemental Information
Interest expense	56,845	58,972
Cash paid for income taxes, net	$ 15,757	$ 33,159