Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net loss	$ (51,983,000)	$ (345,973,000)
Adjustments to reconcile net loss to net cash used in operating activities
Loss from discontinued operations, net of tax	2,955,000	7,947,000
Depreciation and amortization expense	47,818,000	53,033,000
Amortization of operating lease assets	3,285,000	3,632,000
Amortization of debt discount and deferred financing costs	660,000	646,000
Deferred income taxes	2,085,000	(9,128,000)
Stock-based compensation expense	2,607,000	3,268,000
Impairment charge for goodwill	0	262,000,000
Change in fair value of derivative instruments	674,000	380,000
Changes in operating assets and liabilities
Accounts receivable	(3,647,000)	29,057,000
Inventories	(30,238,000)	(51,580,000)
Other assets	(3,851,000)	(335,000)
Accounts payable and accrued expenses	3,322,000	(19,878,000)
Royalties payable and author advances, net	(12,924,000)	(34,816,000)
Deferred revenue	(42,231,000)	(59,529,000)
Interest payable	(6,881,000)	(12,000)
Severance and other charges	(8,156,000)	(5,320,000)
Accrued pension and postretirement benefits	(855,000)	(1,108,000)
Operating lease liabilities	(2,466,000)	(3,304,000)
Other liabilities	(720,000)	(948,000)
Net cash used in operating activities - continuing operations	(100,546,000)	(171,968,000)
Net cash provided by operating activities - discontinued operations	19,290,000	15,201,000
Net cash used in operating activities	(81,256,000)	(156,767,000)
Cash flows from investing activities
Additions to pre-publication costs	(14,354,000)	(18,489,000)
Additions to property, plant, and equipment	(9,949,000)	(11,875,000)
Net cash used in investing activities - continuing operations	(24,303,000)	(30,364,000)
Net cash used in investing activities - discontinued operations	(400,000)	(262,000)
Net cash used in investing activities	(24,703,000)	(30,626,000)
Cash flows from financing activities
Borrowings under revolving credit facility		150,000,000
Payments of long-term debt	(4,750,000)	(4,750,000)
Tax withholding payments related to net share settlements of restricted stock units		(48,000)
Issuance of common stock under employee stock purchase plan	410,000	503,000
Net cash (used in) provided by financing activities - continuing operations	(4,340,000)	145,705,000
Net (decrease) increase in cash and cash equivalents	(110,299,000)	(41,688,000)
Cash and cash equivalents at beginning of the period	281,200,000	296,353,000
Cash and cash equivalents at end of the period	170,901,000	254,665,000
Supplemental disclosure of cash flow information
Interest paid – continuing operations	14,746,000	7,993,000
Interest paid – discontinued operations	5,803,000	7,360,000
Income taxes paid		1,000
Non-cash investing activities
Property, plant, and equipment acquired under finance leases	123,000	288,000
Pre-publication Costs [Member]
Non-cash investing activities
Costs included in accounts payable and accruals	4,392,000	5,978,000
Property, Plant, and Equipment [Member]
Non-cash investing activities
Costs included in accounts payable and accruals	$ 1,452,000	$ 3,787,000