Houghton Mifflin Harcourt (HMHC) 10-K 25 Feb 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Feb. 01, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Document Period End Date	Dec. 31, 2020
Entity Central Index Key	0001580156
Current Fiscal Year End Date	--12-31
Entity Registrant Name	Houghton Mifflin Harcourt Co
Entity Filer Category	Accelerated Filer
Trading Symbol	HMHC
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Shell Company	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Public Float			$ 161.3
Entity Common Stock, Shares Outstanding		126,121,144
Document Transition Report	false
Document Annual Report	true
Entity Small Business	false
Entity Interactive Data Current	Yes
Entity File Number	001-36166
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	27-1566372
Entity Address, Address Line One	125 High Street
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02110
City Area Code	617
Local Phone Number	351-5000
Title of 12(b) Security	Common Stock, $0.01 par value
Security Exchange Name	NASDAQ
Documents Incorporated by Reference	The information required by Part III of this Form 10-K, to the extent not set forth herein, is incorporated herein by reference from the Registrant’s Definitive Proxy Statement for its 2020 Annual Meeting of Stockholders, to be filed with the Securities and Exchange Commission not later than 120 days after December 31, 2020.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 281,200	$ 296,353
Accounts receivable, net of allowances for bad debts and book returns of $18.6 million and $19.7 million, respectively	152,832	184,425
Inventories	166,963	213,059
Prepaid expenses and other assets	19,931	19,257
Total current assets	620,926	713,094
Property, plant, and equipment, net	93,202	100,388
Pre-publication costs, net	203,149	268,197
Royalty advances to authors, net	42,485	44,743
Goodwill	437,977	716,977
Other intangible assets, net	428,584	474,225
Operating lease assets	126,850	132,247
Deferred income taxes	2,415	2,520
Deferred commissions	30,659	29,291
Other assets	34,879	31,490
Total assets	2,021,126	2,513,172
Current liabilities
Current portion of long-term debt	19,000	19,000
Accounts payable	49,104	52,128
Royalties payable	50,771	72,985
Salaries, wages, and commissions payable	21,944	54,938
Deferred revenue	342,605	305,285
Interest payable	11,017	3,826
Severance and other charges	19,590	12,407
Accrued pension benefits	1,593
Accrued postretirement benefits	1,555	1,571
Operating lease liabilities	9,669	8,685
Other liabilities	24,973	24,325
Total current liabilities	551,821	555,150
Long-term debt, net of discount and issuance costs	624,692	638,187
Operating lease liabilities	132,014	134,994
Long-term deferred revenue	562,679	542,821
Accrued pension benefits	24,061	23,648
Accrued postretirement benefits	16,566	15,113
Deferred income taxes	16,411	30,871
Other liabilities	2,419	6,028
Total liabilities	1,930,663	1,946,812
Commitments and contingencies (Note 15)
Stockholders’ equity
Preferred stock, $0.01 par value: 20,000,000 shares authorized; no shares issued and outstanding at December 31, 2020 and 2019
Common stock, $0.01 par value: 380,000,000 shares authorized; 150,459,034 and 148,928,328 shares issued at December 31, 2020 and 2019, respectively; 125,882,000 and 124,351,294 shares outstanding at December 31, 2020 and 2019, respectively	1,505	1,489
Treasury stock, 24,577,034 shares as of December 31, 2020 and 2019, respectively, at cost	(518,030)	(518,030)
Capital in excess of par value	4,918,542	4,906,165
Accumulated deficit	(4,255,830)	(3,775,992)
Accumulated other comprehensive loss	(55,724)	(47,272)
Total stockholders’ equity	90,463	566,360
Total liabilities and stockholders’ equity	$ 2,021,126	$ 2,513,172

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Accounts receivable, allowances for bad debts and book returns	$ 18.6	$ 19.7
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	380,000,000	380,000,000
Common stock, shares issued	150,459,034	148,928,328
Common stock, shares outstanding	125,882,000	124,351,294
Treasury stock, shares	24,577,034	24,577,034

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Net sales	$ 1,031,292,000	$ 1,390,674,000	$ 1,322,417,000
Costs and expenses
Cost of sales, excluding publishing rights and pre-publication Amortization	497,816,000	668,108,000	581,467,000
Publishing rights amortization	20,056,000	26,557,000	34,713,000
Pre-publication amortization	126,180,000	149,515,000	109,257,000
Cost of sales	644,052,000	844,180,000	725,437,000
Selling and administrative	478,101,000	662,606,000	649,295,000
Other intangible asset amortization	25,585,000	25,310,000	26,933,000
Impairment charge for goodwill	279,000,000	0	0
Restructuring/severance and other charges	33,643,000	21,742,000	11,478,000
Gain on sale of assets			(201,000)
Operating loss	(429,089,000)	(163,164,000)	(90,525,000)
Other income (expense)
Retirement benefits non-service (expense) income	(856,000)	167,000	1,280,000
Interest expense	(65,959,000)	(48,778,000)	(45,680,000)
Interest income	899,000	3,157,000	2,550,000
Change in fair value of derivative instruments	672,000	(899,000)	(1,374,000)
Gain on investments	2,091,000
Income from transition services agreement		4,248,000	1,889,000
Loss on extinguishment of debt		(4,363,000)
Loss from continuing operations before taxes	(492,242,000)	(209,632,000)	(131,860,000)
Income tax (benefit) expense for continuing operations	(12,404,000)	4,201,000	5,597,000
Loss from continuing operations	(479,838,000)	(213,833,000)	(137,457,000)
Earnings from discontinued operations, net of tax			12,833,000
Gain on sale of discontinued operations, net of tax			30,469,000
Income from discontinued operations, net of tax			43,302,000
Net loss	$ (479,838,000)	$ (213,833,000)	$ (94,155,000)
Net loss per share attributable to common stockholders
Continuing operations	$ (3.82)	$ (1.72)	$ (1.11)
Discontinued operations			0.35
Net loss	$ (3.82)	$ (1.72)	$ (0.76)
Weighted average shares outstanding
Basic and diluted	125,455,487	124,152,984	123,444,943

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (479,838)	$ (213,833)	$ (94,155)
Other comprehensive (loss) income, net of taxes:
Foreign currency translation adjustments, net of tax	(230)	(511)	(156)
Net change in pension and benefit plan liabilities, net of tax	(9,209)	1,800	(2,056)
Unrealized gain on short-term investments, net of tax		9	9
Net change in unrealized gain (loss) on derivative financial instruments, net of tax	987	(3,386)	3,541
Other comprehensive (loss) income, net of taxes	(8,452)	(2,088)	1,338
Comprehensive loss	$ (488,290)	$ (215,921)	$ (92,817)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities
Net loss	$ (479,838,000)	$ (213,833,000)	$ (94,155,000)
Adjustments to reconcile net loss to net cash provided by operating activities
Earnings from discontinued operations, net of tax			(12,833,000)
Gain on sale of discontinued operations, net of tax			(30,469,000)
Gain on sale of assets			(201,000)
Depreciation and amortization expense	236,489,000	272,692,000	250,466,000
Operating lease assets, amortization and impairments	5,397,000	15,949,000
Amortization of debt discount and deferred financing costs	6,004,000	4,286,000	4,181,000
Gain on investments	(2,091,000)
Deferred income taxes	(14,355,000)	4,535,000	5,140,000
Stock-based compensation expense	11,573,000	13,968,000	13,248,000
Impairment charge for goodwill	279,000,000	0	0
Loss on extinguishment of debt		4,363,000
Change in fair value of derivative instruments	(672,000)	899,000	1,374,000
Changes in operating assets and liabilities, net of acquisitions
Accounts receivable	31,593,000	19,182,000	(11,005,000)
Inventories	46,096,000	(28,850,000)	(33,515,000)
Other assets	(11,425,000)	(20,155,000)	3,908,000
Accounts payable and accrued expenses	(34,941,000)	(12,136,000)	16,144,000
Royalties payable and author advances, net	(19,956,000)	9,342,000	(1,650,000)
Deferred revenue	57,178,000	200,473,000	(7,692,000)
Interest payable	7,191,000	3,690,000	(186,000)
Severance and other charges	7,183,000	10,631,000	(2,823,000)
Accrued pension and postretirement benefits	3,443,000	(4,800,000)	(904,000)
Operating lease liabilities	(1,996,000)	(17,281,000)
Other liabilities	(10,625,000)	(7,980,000)	5,056,000
Net cash provided by operating activities—continuing operations	115,248,000	254,975,000	104,084,000
Net cash provided by operating activities—discontinued operations			10,831,000
Net cash provided by operating activities	115,248,000	254,975,000	114,915,000
Cash flows from investing activities
Proceeds from sales and maturities of short-term investments		50,000,000	86,539,000
Purchases of short-term investments			(49,553,000)
Additions to pre-publication costs	(61,331,000)	(102,562,000)	(123,403,000)
Additions to property, plant, and equipment	(50,940,000)	(37,561,000)	(53,741,000)
Proceeds from sale of business			140,000,000
Acquisition of business, net of cash acquired		(5,447,000)
Investment in preferred stock		(750,000)	(500,000)
Proceeds from sale of assets			1,085,000
Net cash (used in) provided by investing activities—continuing operations	(112,271,000)	(96,320,000)	427,000
Net cash used in investing activities—discontinued operations			(6,832,000)
Net cash used in investing activities	(112,271,000)	(96,320,000)	(6,405,000)
Cash flows from financing activities
Borrowings under revolving credit facility	150,000,000	60,000,000	50,000,000
Payments of revolving credit facility	(150,000,000)	(60,000,000)	(50,000,000)
Payments of long-term debt	(19,000,000)	(772,000,000)	(8,000,000)
Payments of deferred financing fees		(8,493,000)
Tax withholding payments related to net share settlements of restricted stock units and awards	(48,000)	(2,018,000)	(1,190,000)
Issuance of common stock under employee stock purchase plan	918,000	1,028,000	1,263,000
Net collections under transition service agreement		1,136,000	3,803,000
Net cash used in financing activities—continuing operations	(18,130,000)	(115,667,000)	(4,124,000)
Net (decrease) increase in cash and cash equivalents	(15,153,000)	42,988,000	104,386,000
Cash and cash equivalents at the beginning of the period	296,353,000	253,365,000	148,979,000
Cash and cash equivalents at the end of the period	281,200,000	296,353,000	253,365,000
Supplemental disclosure of cash flow information
Interest paid	52,942,000	41,059,000	41,758,000
Income taxes paid	1,883,000	671,000	430,000
Non-cash investing activities
Property, plant, and equipment acquired under finance leases	164,000	327,000	480,000
Term Loan [Member]
Cash flows from financing activities
Proceeds from long-term debt, net of discount		364,800,000
Senior Secured Notes [Member]
Cash flows from financing activities
Proceeds from long-term debt, net of discount		299,880,000
Pre-publication Costs [Member]
Non-cash investing activities
Costs included in accounts payable and accruals	5,282,000	5,480,000	13,974,000
Property, Plant, and Equipment [Member]
Non-cash investing activities
Costs included in accounts payable and accruals	$ 2,002,000	$ 3,039,000	$ 1,908,000

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Treasury Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Deficit [Member]	Accumulated Deficit [Member]Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning balance at Dec. 31, 2017	$ 795,193	$ 52,711	$ 1,479	$ (518,030)	$ 4,879,793	$ (3,521,527)	$ 52,711	$ (46,522)
Beginning balance, shares at Dec. 31, 2017			147,911,466
Accounting Standards Update Extensible List	us-gaap:AccountingStandardsUpdate201409Member
Net loss	$ (94,155)					(94,155)
Other comprehensive income (loss), net of tax	1,338							1,338
Issuance of common stock for employee purchase plan	1,613		$ 2		1,611
Issuance of common stock for employee purchase plan, shares			175,428
Issuance of common stock for vesting of restricted stock units			$ 3		(3)
Issuance of common stock for vesting of restricted stock units, shares			346,255
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units	(1,190)				(1,190)
Restricted stock forfeitures and cancellations			$ (3)		3
Restricted stock forfeitures and cancellations, shares			(268,295)
Stock-based compensation expense	12,960				12,960
Ending balance at Dec. 31, 2018	$ 768,470	$ 812	$ 1,481	(518,030)	4,893,174	(3,562,971)	$ 812	(45,184)
Ending balance, shares at Dec. 31, 2018			148,164,854
Accounting Standards Update Extensible List	us-gaap:AccountingStandardsUpdate201602Member
Net loss	$ (213,833)					(213,833)
Other comprehensive income (loss), net of tax	(2,088)							(2,088)
Issuance of common stock for employee purchase plan	1,438		$ 2		1,436
Issuance of common stock for employee purchase plan, shares			186,114
Issuance of common stock for vesting of restricted stock units			$ 6		(6)
Issuance of common stock for vesting of restricted stock units, shares			577,360
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units	(2,018)				(2,018)
Stock-based compensation expense	13,579				13,579
Ending balance at Dec. 31, 2019	566,360		$ 1,489	(518,030)	4,906,165	(3,775,992)		(47,272)
Ending balance, shares at Dec. 31, 2019			148,928,328
Net loss	(479,838)					(479,838)
Other comprehensive income (loss), net of tax	(8,452)							(8,452)
Issuance of common stock for employee purchase plan	1,247		$ 4		1,243
Issuance of common stock for employee purchase plan, shares			380,757
Issuance of common stock for vesting of restricted stock units			$ 12		(12)
Issuance of common stock for vesting of restricted stock units, shares			1,149,949
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units	(48)				(48)
Stock-based compensation expense	11,194				11,194
Ending balance at Dec. 31, 2020	$ 90,463		$ 1,505	$ (518,030)	$ 4,918,542	$ (4,255,830)		$ (55,724)
Ending balance, shares at Dec. 31, 2020			150,459,034

Basis of Presentation

Basis of Presentation	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	1. Houghton Mifflin Harcourt Company (“HMH,” “Houghton Mifflin Harcourt,” “we,” “us,” “our,” or the “Company”) is a learning technology company, committed to delivering connected solutions that engage learners, empower educators and improve student outcomes. As a leading provider of Kindergarten through 12 th We are organized along two business segments: Education and HMH Books & Media. Within our Education segment, we focus on the K-12 market and, in the United States, we are a market leader. We specialize in comprehensive core curriculum, supplemental and intervention solutions, and we provide ongoing support in professional learning and coaching for educators and administrators. Our offerings are rooted in learning science, and we work with research partners, universities and third-party organizations as we design, build, implement and iterate our offerings to maximize their effectiveness. We are purposeful about innovation, leveraging technology to create engaging and immersive experiences designed to deepen learning experiences for students and to extend teachers’ capabilities so that they can focus on making meaningful connections with their students. Our diverse portfolio enables us to help ensure that every student and teacher has the tools needed for success. We are able to build deep partnerships with school districts and leverage the scope of our offerings to provide holistic solutions at scale with the support of our far-reaching sales force and talented field-based specialists and consultants. We provide print, digital, and blended print/digital solutions that are tailored to a district’s needs, goals and technological readiness. Furthermore, for nearly two centuries, our HMH Books & Media segment has brought renowned and awarded children’s, fiction, non-fiction, culinary and reference titles to readers throughout the world. Our distinguished author list includes ten Nobel Prize winners, forty-nine Pulitzer Prize winners, and twenty-six National Book Award winners. We are home to popular characters and titles such as Curious George, Carmen Sandiego, The Lord of the Rings, The Whole30, The Polar Express, The consolidated financial statements of HMH include the accounts of all of our wholly-owned subsidiaries as of December 31, 2020 and 2019 and for the periods ended December 31, 2020, 2019 and 2018. The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Our accompanying consolidated financial statements include the results of operations of the Company and our wholly-owned subsidiaries. All material intercompany accounts and transactions are eliminated in consolidation. We expect our net cash provided by operations combined with our cash and cash equivalents and borrowing availability under our revolving credit facility to provide sufficient liquidity to fund our current obligations, capital spending, debt service requirements and working capital requirements over at least the next twelve months. The ability of the Company to fund planned operations is based on assumptions which involve significant judgment and estimates of future revenues, capital spend and other operating costs. Seasonality and Comparability Our net sales, operating profit or loss and net cash provided by or used in operations are impacted by the inherent seasonality of the academic calendar, which typically results in a cash flow usage in the first half of the year and a cash flow generation in the second half of the year. Consequently, the performance of our businesses may not be comparable quarter to consecutive quarter and should be considered on the basis of results for the whole year or by comparing results in a quarter with results in the same quarter for the previous year. Moreover, uncertainty resulting from the COVID-19 pandemic may result in not following this historic pattern. Approximately 81% of our net sales for the year ended December 31, 2020 were derived from our Education segment, which is a markedly seasonal business. Schools conduct the majority of their purchases in the second and third quarters of the calendar year in preparation for the beginning of the school year. Thus, for the years ended December 31, 2020, 2019 and 2018, approximately 66% of our consolidated net sales were realized in the second and third quarters. Sales of K-12 instructional materials and customized testing products are also cyclical with some years offering more sales opportunities than others in light of the state adoption calendar. The amount of funding available at the state level for educational materials also has a significant effect on year-to-year net sales. Although the loss of a single customer would not have a material adverse effect on our business, schedules of school adoptions and market acceptance of our products can materially affect year-to-year net sales performance.

Impact of the COVID-19 Pandemic

Impact of the COVID-19 Pandemic	12 Months Ended
	Dec. 31, 2020
Extraordinary And Unusual Items [Abstract]
Impact of the Covid-19 Pandemic	2. Impact of the COVID-19 Pandemic The unprecedented and rapid spread of COVID-19 and the resulting social distancing measures, including business and school closures implemented by federal, state and local authorities, significantly reduced customer demand for our solutions and services, disrupted portions of our supply chain and warehousing operations and also disrupted our ability to deliver our educational solutions and services. We continue to monitor indicators of demand, including our sales pipeline, customer orders and product shipments, as well as observe the impact to state revenues and related educational budgets to ascertain an estimate of the impact; however, the length and severity of the reduction in demand due to the pandemic remains uncertain. Accordingly, our full year results for 2020 were adversely impacted compared to prior years. While we are planning for a demand recovery, the exact timing and pace of recovery is uncertain given the significant disruption caused by the pandemic on the operations of our customers. Our expense management and liquidity measures may be modified as we obtain additional clarity on the timing of customer demand recovery. In response to these developments, we have implemented measures to help mitigate the impact on our financial position and operations. These measures include, but are not limited to, the following: Expense Management. With the reduction in net sales, we have, and will continue to implement cost saving initiatives, including: • director, executive and senior leadership salary reductions, and for the majority of employees, a four-day work week with associated labor cost reductions, in each case beginning in April 2020 and ceasing near the end of July 2020. The costs associated with ending the furlough program and the salary reductions were subsequently mitigated by the 2020 Restructuring Plan discussed below; • a freeze on spending not directly tied to near-term billings, including a reduction in all discretionary spending such as marketing, advertising, travel, and office supplies; • executing a voluntary early retirement incentive program in September 2020, as discussed below; and • commencing a restructuring program in September 2020 including a reduction in force, as discussed below. Balance Sheet, Cash Flow and Liquidity. In addition to the expense management actions noted above, we have taken the following actions to increase liquidity and strengthen our financial position, including: • reduced inventory purchasing; • deferred long-term capital projects not directly contributing to billings in 2020; and • deferred the payment of our employer payroll taxes allowed under the Coronavirus Aid, Relief, and Economic Security (“CARES”) Act. The deferred amounts under the CARES Act were repaid in full in December 2020 as a result of the success of the cash and expense mitigation efforts. 2020 Restructuring Plan . On September 4, 2020, we completed a voluntary retirement incentive program, which was offered to On September 30, 2020, we undertook a restructuring program, including a reduction in force, as part of the ongoing assessment of our cost structure amid the COVID-19 pandemic and in line with our strategic transformation plan. The reduction in force resulted in a 22% reduction in our workforce, including positions eliminated as part of the voluntary retirement incentive program mentioned above, and net of newly created positions to support our digital first operations. The reduction in force resulted in the departure of approximately 525 employees and was completed in October 2020. Each of the employees received or will receive separation payments in accordance with our severance policy. The total one-time, non-recurring cost incurred in connection with the restructuring program, inclusive of the voluntary retirement incentive program (collectively the “2020 Restructuring Plan”), all of which represents cash expenditures, is approximately $33.6 million. Forward-looking After reviewing our ability to meet future financial obligations over the next twelve months, including consideration of our recent actions described above, we have concluded our net cash from operations combined with our cash and cash equivalents and borrowing availability under our revolving credit facility provide sufficient liquidity to fund our current obligations, capital spending, debt service requirements and working capital requirements over at least the next twelve months. Our primary credit facilities do not require us to comply with financial maintenance covenants. The ability of the Company to fund planned operations is based on assumptions which involve significant judgment and estimates of future revenues, capital spend and other operating costs. Our current assumptions are that our industry will begin to recover as school districts become, or continue being, fully operational, either in-person, fully remote or hybrid, and we have performed a sensitivity analysis on these assumptions to forecast the impact of a slower-than-anticipated recovery. Based on the actions enacted in 2020 described earlier, we have concluded we have sufficient liquidity to fund our current obligations, capital spending, debt service requirements and working capital requirements over at least the next twelve months. Valuation of Goodwill, Indefinite-Lived Intangible Assets and Long-Lived Assets We perform an impairment test to assess the carrying value of goodwill and indefinite-lived intangible assets on an annual basis (as of October 1) and, if certain events or circumstances indicate that an impairment loss may have been incurred, on an interim basis. Our fourth quarter 2020 impairment tests of goodwill and indefinite-lived intangible assets did not indicate an impairment existed as the fair value exceeded our carrying values. During the three months ended March 31, 2020, our stock price declined to historical lows since our 2013 initial public offering. We determined that the significant decline in our market capitalization and broader economic downturn arising from the COVID-19 pandemic We concluded that quantitative analyses were required to be performed due to the triggering event occurring during the first quarter of 2020. G oodwill is allocated entirely to our Education reporting unit. We utilized an implied market value method under the market approach to calculate the fair value of the Education reporting unit as of March 31, 2020, which we determined was the best approximation of fair value of the Education reporting unit in the current social and economic environment. We have previously used a combination of the implied market value method and guideline public company method approach. The relevant inputs and assumptions used in the valuation of the Education reporting unit include our market capitalization, selection of a control premium, and the determination of an appropriate market multiple to value the HMH Books & Media reporting unit, as well as the fair value of individual assets and liabilities. Based on our interim impairment assessment, we concluded that our goodwill, which is wholly attributed to the Education reporting unit, was impaired and, accordingly, recorded a goodwill impairment charge of $279.0 million. With the continuation of the COVID-19 pandemic and the associated downward pressure on our billings, we concluded that impairment triggering events existed as of September 30, 2020. Accordingly, we estimated the fair value of the Education reporting unit as of September 30, 2020 utilizing the implied market value method. Using consistent relative inputs and assumptions as described above with respect to the first quarter 2020 testing, we concluded that no impairment existed as of September 30, 2020. The fair value of the Education reporting unit as of September 30, 2020 exceeded its carrying value by approximately 18%. During the fourth quarter of 2020, we recorded an adjustment of $17.0 million and $1.0 million to increase both the goodwill impairment charge and income tax benefit recorded, respectively, to correct an error of the previously recorded goodwill impairment of $262.0 million and related income tax benefit in the first quarter of 2020. Management believes these adjustments are not material to the current period financial statements or any prior periods. Additionally, as a result of the triggering events identified in the first and third quarters, we performed quantitative impairment analyses over our indefinite-lived intangible assets and long-lived assets. With regards to indefinite-lived intangible assets, which includes the Houghton Mifflin Harcourt tradename, the recoverability was evaluated using a one-step process whereby we determined the fair value by asset and then compared it to its carrying value to determine if the asset was impaired. We estimated the fair value by preparing a relief-from-royalty discounted cash flow analysis using forward looking revenue projections. The significant assumptions used in discounted cash flow analysis included: future net sales, a long-term growth rate, a royalty rate and a discount rate used to present value future cash flows. The discount rate was based on the weighted-average cost of capital method at the date of the evaluation. The fair value of the indefinite-lived intangible assets was in excess of its carrying value by approximately 12% as of March 31, 2020 and 18% as of September 30, 2020, respectively, and substantially exceeded its carrying value as of October 1, 2019. We also performed an impairment test on our long-lived assets using an undiscounted cash flow model in determining the fair value, which was then compared to book value of the asset groups evaluated. The long-lived impairment analysis was performed over the Education reporting unit and the HMH Books & Media reporting unit. Estimates and significant assumptions included in the long-lived asset impairment analysis included identification of the primary asset in each asset group and undiscounted cash flow projections. We concluded that our indefinite-lived intangible assets and long-lived assets were not impaired based on the results of the quantitative analyses performed. Depending on how long the economic and social conditions resulting from the COVID-19 pandemic exist and their future impact on state and local budgets with regards to educational spending, as well as discretionary consumer spending, we may be subject to further impairments in the future.

Significant Accounting Policies

Significant Accounting Policies and Recent Accounting Standards	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Significant Accounting Policies and Recent Accounting Standards	3. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires the use of estimates, assumptions and judgments by management that affect the reported amounts of assets, liabilities, revenues, expenses, and related disclosure of contingent assets and liabilities in the amounts reported in the financial statements and accompanying notes. On an ongoing basis, we evaluate our estimates and assumptions including, but not limited to, book returns, deferred revenue and related standalone selling price estimates, allowance for bad debts, recoverability of advances to authors, valuation of inventory, financial instruments valuation, income taxes, pensions and other postretirement benefits obligations, contingencies, litigation, depreciation and amortization periods, and the recoverability of long-term assets such as property, plant, and equipment, capitalized pre-publication costs, other identified intangibles and goodwill. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets, liabilities and equity and the amount of revenues and expenses. The full extent to which the COVID-19 pandemic will directly or indirectly impact our business, results of operations and financial condition will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat it, as well as the economic impact on local, regional, national and international customers and markets. Actual results may differ from those estimates. Revenue Recognition Revenue is recognized when a customer obtains control of promised goods or services, in an amount that reflects the consideration which we expect to receive in exchange for those goods or services. To determine revenue recognition for arrangements that we determine are within the scope of the new revenue recognition accounting standard, we perform the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. At contract inception, we assess the goods or services promised within each contract and determine those that are performance obligations and assess whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Revenue is measured as the amount of consideration we expect to receive in exchange for transferring products or services to a customer. To the extent the transaction price includes variable consideration, which generally reflects estimated future product returns, we estimate the amount of variable consideration that should be included in the transaction price utilizing the expected value method to which we expect to be entitled. Variable consideration is included in the transaction price if, in our judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Estimates of variable consideration and the determination of whether to include estimated amounts in the transaction price are based largely on all information (historical, current and forecasted) that is reasonably available. Sales, value add, and other taxes collected on behalf of third parties are excluded from revenue. We estimate the collectability of contracts upon execution. For contracts with rights of return, the transaction price is adjusted to reflect the estimated returns for the arrangement on these sales and is made at the time of sale based on historical experience by product line or customer. The transaction prices allocated are adjusted to reflect expected returns and are based on historical return rates and sales patterns. Shipping and handling fees charged to customers are included in net sales. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. We do not assess whether a significant financing component exists if the period between when we perform our obligations under the contract and when the customer pays is one year or less. Significant financing components’ income is included in interest income. Contracts are sometimes modified to account for changes in contract specifications and requirements. Contract modifications exist when the modification either creates new, or changes the existing, enforceable rights and obligations. Generally, contract modifications are for products or services that are not distinct from the existing contract due to the inability to use, consume or sell the products or services on their own to generate economic benefits and are accounted for as if they were part of that existing contract. The effect of such a contract modification on the transaction price and measure of progress for the performance obligation to which it relates is recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. Physical product revenue is recognized when the customer obtains control of our product, which occurs at a point in time, and may be upon shipment or upon delivery based on the contractual shipping terms of a contract. Revenues from static digital content commence upon delivery to the customer of the digital entitlement that is required to access and download the content and is typically recognized at a point in time. Revenues from subscription software licenses, related hosting services and product support are recognized evenly over the license term as we believe this best represents the pattern of transfer to the customer. The perpetual software licenses provide the customer with a functional license to our products and their related revenues are recognized when the customer receives entitlement to the software. For the technical services provided to customers in connection with the software license, including hosting services related to perpetual licenses, we recognize revenue upon delivery of the services. As the invoices are based on each day of service, this is directly linked to the transfer of benefit to the customer. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. We enter into certain contracts that have multiple performance obligations, one or more of which may be delivered subsequent to the delivery of other performance obligations. These performance obligations may include print and digital media, professional development services, training, software licenses, access to hosted content, and various services related to the software including, but not limited to hosting, maintenance and support, and implementation. We allocate the transaction price based on the estimated relative standalone selling prices of the promised products or services underlying each performance obligation. We determine standalone selling prices based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, we estimate the standalone selling price taking into account available information such as market conditions and internally approved standard pricing discounts related to the performance obligations. Generally, our performance obligations include print and digital textbooks and instructional materials, trade books, reference materials, formative assessment materials and multimedia instructional programs; licenses to book rights and content; access to hosted content; and services including professional development, consulting and training. Our contracts may also contain software performance obligations including perpetual and subscription-based licenses and software maintenance and support services. Accounts Receivable Accounts receivable include amounts billed and currently due from customers and are recorded net of allowances for doubtful accounts and reserves for returns. In the normal course of business, we extend credit to customers that satisfy predefined criteria. We estimate the collectability of our receivables and develop those estimates to reflect the risk of credit loss. Allowances for doubtful accounts are established through the evaluation of accounts receivable aging, prior collection experience, current conditions and reasonable and supportable forecasts of the economic conditions that will exist through the contractual life of the financial asset. We monitor our ongoing credit exposure through an active review of collection trends and specific facts and circumstances. Our activities include monitoring the timeliness of payment collection and performing timely account reconciliations. Contract Assets Contract assets include unbilled amounts where revenue is recognized over time as the services are delivered to the customer based on the extent of progress towards completion and revenue recognized exceeds the amount billed to the customer, and right of payment is not subject to the passage of time. Amounts may not exceed their net realizable value. Contract assets are included in prepaid expenses and other assets on our consolidated balance sheets. Deferred Commissions Our incremental direct costs of obtaining a contract, which consist of sales commissions, are deferred and amortized over the period of contract performance. Applying the practical expedient, we recognize sales commission expense when incurred if the amortization period of the assets that we otherwise would have recognized is one year or less. Amortization expense is included in selling and administrative expenses. Deferred Revenue Our contract liabilities consist of advance payments and billings in excess of revenue recognized and are classified as deferred revenue on our consolidated balance sheets. Our contract assets and liabilities are accounted for and presented on a net basis as either a contract asset or contract liability at the end of each reporting period. We classify deferred revenue as current or noncurrent based on the timing of when we expect to recognize revenue. In order to determine revenue recognized in the period from contract liabilities, we first allocate revenue to the individual contract liability balance outstanding at the beginning of the period until the revenue exceeds that balance. If additional advances are received on those contracts in subsequent periods, we assume all revenue recognized in the reporting period first applies to the beginning contract liability as opposed to a portion applying to the new advances for the period. Advertising Costs and Sample Expenses Advertising costs are charged to selling and administrative expenses as incurred. Advertising costs were $12.1 Cash and Cash Equivalents Cash and cash equivalents consist primarily of cash in banks and highly liquid investment securities that have maturities of three months or less when purchased. The carrying amount of cash equivalents approximates fair value because of the short-term maturity of these investments. Accounts Receivable Accounts receivable are recorded net of allowances for doubtful accounts and reserves for returns. In the normal course of business, we extend credit to customers that satisfy predefined criteria. We estimate the collectability of our receivables. Allowances for doubtful accounts are established through the evaluation of accounts receivable aging and prior collection experience to estimate the ultimate collectability of these receivables. Reserves for returns are based on historical return rates and sales patterns. Inventories Inventories are stated at the lower of weighted-average cost or net realizable value. The level of obsolete and excess inventory is estimated on a program or title level-basis by comparing the number of units in stock with past usage and the expected future demand. The expected future demand of a program or title is determined by the copyright year, the previous year’s usage, the subsequent years’ sales forecast, and known forward-looking trends including our development cycle to replace the title or program and competing titles or programs. Property, Plant, and Equipment Property, plant, and equipment are stated at cost, or in the case of assets acquired in business combinations, at fair value as of the acquisition date, less accumulated depreciation. Equipment under capital lease is stated at fair value at inception of the lease, less accumulated depreciation. Maintenance and repair costs are charged to expense as incurred, and renewals and improvements that extend the useful life of the assets are capitalized. Costs associated with developing film and episodic series assets are deferred if such amounts are expected to be recovered through future revenues. Film and episodic series costs are amortized on a pro rata basis of revenue earned and total revenue expected to be earned from the film or episodic series. Depreciation on property, plant, and equipment is calculated using the straight-line method over the estimated useful lives of the assets or, in the case of assets acquired in business combinations, over their remaining lives. Equipment held under capital leases and leasehold improvements are amortized using the straight-line method over the shorter of the lease term or estimated useful life of the asset. Estimated useful lives of property, plant, and equipment are as follows: Estimated Useful Life Building and building equipment 10 to 35 years Machinery and equipment 2 to 15 years Capitalized software and internal-use software 3 to 5 years Leasehold improvements Lesser of useful life or lease term Film and media Revenue earned Capitalized Internal-Use Software and Software Development Costs Capitalized internal-use software and software is included in property, plant and equipment on the consolidated balance sheets. We capitalize certain costs related to obtaining or developing computer software for internal use including external customer-facing websites. Costs incurred during the application development stage, including external direct costs of materials and services, and payroll and payroll related costs for employees who are directly associated with the internal-use software project, are capitalized and amortized on a straight-line basis over the expected useful life of the related software. The application development stage includes design of chosen path, software configuration and integration, coding, hardware installation and testing. Costs incurred during the preliminary project stage, as well as maintenance, training and upgrades that do not result in additional functionality subsequent to general release are expensed as incurred. Certain computer software development costs for software that is to be sold or marketed are capitalized in the consolidated balance sheets. Capitalization of computer software development costs begins upon the establishment of technological feasibility. We define the establishment of technological feasibility as a working model. Amortization of capitalized computer software development costs is provided on a product-by-product basis using the straight-line method, beginning upon commercial release of the product and continuing over the remaining estimated economic life of the product. The carrying amounts of computer software development costs are annually compared to net realizable value and impairment charges are recorded, as appropriate, when amounts expected to be realized are lower. We review internal-use software and software development costs for impairment. For the years ended December 31, 2020, 2019 and 2018, there was no impairment of internal-use software and software developments costs. Pre-publication Costs We capitalize the art, prepress, manuscript and other costs incurred in the creation of the master copy of a book or other media (the “pre-publication costs”). Pre-publication costs are primarily amortized from the year of sale over five years using the sum-of-the-years-digits method, which is an accelerated method for calculating an asset’s amortization. Under this method, the amortization expense recorded for a pre-publication cost asset is approximately 33% (year 1), 27% (year 2), 20% (year 3), 13% (year 4) and 7% (year 5). This policy is used throughout the Company, except for the HMH Books & Media young readers and general interest books, which generally expenses such costs as incurred. Additionally, pre-publication costs recorded in connection with the acquisition of the EdTech business are amortized over 7 years on a projected sales pattern. The amortization methods and periods chosen best reflects the pattern of expected sales generated from individual titles or programs. We periodically evaluate the remaining lives and recoverability of capitalized pre-publication costs, which are often dependent upon program acceptance by state adoption authorities. Amortization expense related to pre-publication costs for the years ended December 31, 2020, 2019 and 2018 were $126.2 million, $149.5 million and $109.3 million, respectively. We review pre-publication costs for impairment. Goodwill and Indefinite-lived Intangible Assets Goodwill is the excess of the purchase price paid over the fair value of the net assets of the business acquired. Other intangible assets principally consist of branded trademarks and trade names, acquired publishing rights and customer relationships. Goodwill and indefinite-lived intangible assets (certain tradenames) are not amortized, but are reviewed at least annually for impairment or earlier, if an indication of impairment exists. Goodwill is allocated entirely to our Education reporting unit. Determining the fair value of a reporting unit is judgmental in nature and involves the use of significant estimates and assumptions. These estimates and assumptions include our market capitalization, selection of a control premium, and the determination of appropriate market comparables as well as the fair value of certain individual assets and liabilities. We have the option of first assessing qualitative factors to determine whether it is necessary to perform a quantitative impairment test for goodwill or we can perform the quantitative impairment test without performing the qualitative assessment. In performing the qualitative assessment, events and circumstances specific to the reporting unit and to the entity as a whole, such as macroeconomic conditions, industry and market considerations, overall financial performance and cost factors are considered when evaluating whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. If the fair value of a reporting unit exceeds the carrying value of the net assets assigned to a reporting unit, goodwill is considered not impaired and no further testing is required. If the carrying value of the net assets assigned to a reporting unit exceeds the fair value of a reporting unit, goodwill is deemed impaired and is written down to the extent of the difference between the fair value of the reporting unit and the carrying value We estimate the total fair value of the Education reporting unit by using one or more of various valuation techniques including an evaluation of our market capitalization and peer company multiples depending on the best approximation of fair value of the Education reporting unit in the current social and economic environment. With regard to indefinite-lived intangible assets, which includes the Houghton Mifflin Harcourt tradename at December 31, 2020 and 2019, the recoverability is evaluated using a one-step process whereby we determine the fair value by asset and then compare it to its carrying value to determine if the asset is impaired. We estimate the fair value by preparing a relief-from-royalty discounted cash flow analysis using forward looking revenue projections. The significant assumptions used in discounted cash flow analysis include: future net sales, a long-term growth rate, a royalty rate and a discount rate used to present value future cash flows and the terminal value of the Education reporting unit. The discount rate is based on the weighted-average cost of capital method at the date of the evaluation. Adverse changes in our market capitalization or peer company multiples by an equivalent amount could give rise to an impairment. We completed our annual goodwill impairment test as of October 1, 2020 using consistent methodologies and assumptions with those described during our event-driven tests We completed our annual indefinite-lived asset impairment tests as of October 1, 2020 and 2019. No indefinite-lived intangible assets were deemed to be impaired for the years ended December 31, 2020, 2019 and 2018. Publishing Rights A publishing right is an acquired right that allows us to publish and republish existing and future works as well as create new works based on previously published materials. We determined the fair market value of the publishing rights arising from business combinations by discounting the after-tax cash flows projected to be derived from the publishing rights and titles to their net present value using a rate of return that accounts for the time value of money and the appropriate degree of risk. The useful life of the publishing rights is based on the lives of the various copyrights involved. We calculate amortization using the percentage of the projected operating income before taxes derived from the titles in the current year as a percentage of the total estimated operating income before taxes over the remaining useful life. Acquired publication rights, as well as customer-related intangibles with definitive lives, are primarily amortized on an accelerated basis over periods ranging from 3 to 20 years. We review our publishing rights for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. No publishing rights were deemed to be impaired for the years ended December 31, 2020, 2019 and 2018. Impairment of Other Long-lived Assets We review our other long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. If the future undiscounted cash flows are less than their book value, impairment exists. The impairment is measured as the difference between the book value and the fair value of the underlying asset. Fair value is normally determined using an undiscounted cash flow model. Severance We accrue postemployment benefits if the obligation is attributable to services already rendered, rights to those benefits accumulate, payment of benefits is probable, and amount of benefit is reasonably estimated. Postemployment benefits include severance benefits. Subsequent to recording such accrued severance liabilities, changes in market or other conditions may result in changes to assumptions upon which the original liabilities were recorded that could result in an adjustment to the liabilities. Royalty Advances Royalty advances to authors are capitalized and represent amounts paid in advance of the sale of an author’s product and are recovered as earned. As advances are recorded, a partial reserve may be recorded immediately based primarily upon historical sales experience. Additionally, advances are evaluated periodically to determine if they are expected to be recovered on a title-by-title basis, with consideration given to the other titles in the author’s portfolio also earning against the outstanding advance. Any portion of a royalty advance that is not expected to be recovered is fully reserved. The reserve for royalty advances is reported as a reduction of the royalty advances to authors balance. Leases On January 1, 2019, we adopted the new lease accounting standard using the modified retrospective method. We applied the guidance to each lease as of January 1, 2019 with a cumulative effect adjustment to the opening balance of accumulated deficit as of that date. The standard requires lessees to recognize a lease liability and a right of use asset on the balance sheet for operating leases. Right of use assets represent our right to use an underlying asset for the lease term, and lease liabilities represent our obligation to make lease payments arising from the lease. Right of use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. Accounting for finance leases is substantially unchanged. Prior comparative periods were not adjusted. We elected the package of practical expedients permitted under the transition guidance within the new standard, which allowed us to not reassess whether any expired or existing contracts are or contain leases, carry forward the historical lease classification and to not reassess initial direct costs for any existing leases. We did not elect the hindsight practical expedient to determine the lease term for existing leases. Upon implementation of the new guidance, we have elected the practical expedients to combine lease and non-lease components, and to not recognize right of use assets and lease liabilities for short-term leases. The adoption of this guidance impacted our consolidated balance sheets due to the recognition of the lease rights and obligations related to our office space, automobile fleet and office equipment leases as assets and liabilities of approximately $148.0 million and $161.0 million, respectively. The adjustment to accumulated deficit of approximately $0.8 million related to a previously recorded deferred gain on the sale leaseback of a warehouse. The impact on our results of operations and cash flows was not material. Under the new lease accounting standard, we determine if an arrangement is a lease at inception. Right of use assets and lease liabilities are recognized at commencement date based on the present value of remaining lease payments over the lease term. For this purpose, we consider only payments that are fixed and determinable at the time of commencement. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. Our incremental borrowing rate is a hypothetical rate based on our understanding of what our credit rating would be. The right of use asset also includes any lease payments made prior to commencement and is recorded net of any lease incentives received. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise such options. When determining the probability of exercising such options, we consider contract-based, asset-based, entity-based, and market-based factors. Our lease agreements may contain variable costs such as common area maintenance, insurance, real estate taxes or other costs. Variable lease costs are expensed as incurred on our consolidated statements of operations. Our lease agreements generally do not contain any residual value guarantees or restrictive covenants. Operating leases are included in operating lease assets and operating lease liabilities on our consolidated balance sheets. Finance leases are included in property, plant, and equipment, and other liabilities on our consolidated balance sheets. Income Taxes We record income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax basis, and operating loss and tax credit carryforwards. Our consolidated financial statements contain certain deferred tax assets which have arisen primarily as a result of interest expense limitations, as well as other temporary differences between financial and tax accounting. We establish a valuation allowance if the likelihood of realization of the deferred tax assets is reduced based on an evaluation of objectively verifiable evidence. Significant management judgment is required in determining our provision for income taxes, our deferred tax assets and liabilities and any valuation allowance recorded against those deferred tax assets. We evaluate the weight of all available evidence to determine whether it is more likely than not that some portion or all of the deferred income tax assets will not be realized. We also evaluate any uncertain tax positions and only recognize the tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50 percent likelihood of being realized upon settlement. We record a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. Any change in judgment related to the expected ultimate resolution of uncertain tax positions is recognized in earnings in the period in which such change occurs. Interest and penalties, if any, related to unrecognized tax benefits are recorded in income tax expense. Stock-Based Compensation Certain employees and directors have been granted stock options, restricted stock and restricted stock units in our common stock. Stock-based compensation expense reflects the fair value of stock-based awards measured at the grant date and recognized over the relevant service period. We estimate the fair value of each stock-based award on the measurement date using the current market price based on the target value of the award for restricted stock and restricted stock units, the Monte Carlo simulation for market-based restricted stock units and the Black-Scholes valuation model for stock options. We recognize stock-based compensation expense over the awards requisite service period on a straight-line basis for time-based stock options, restricted stock and restricted stock units and on a graded basis for restricted stock and restricted stock units that are contingent on the achievement of performance conditions. Comprehensive Loss Comprehensive loss is defined as changes in the equity of an enterprise except those resulting from stockholder transactions. The amounts shown on the consolidated statements of stockholders’ equity and comprehensive loss relate to the cumulative effect of changes in pension and postretirement liabilities, foreign currency translation gain and loss adjustments, unrealized gains and losses on short-term investments and gains and losses on derivative instruments. Foreign Currency Translation The functional currency for each of our subsidiaries is the currency of the primary economic environment in which the subsidiary operates, generally defined as the currency in which the entity generates and expends cash. Foreign currency denominated assets and liabilities are translated into United States dollars at current rates as of the balance sheet date and the revenue, costs and expenses are translated at the average rates established during each reporting period. Cumulative translation gains or losses are recorded in equity as an element of accumulated other comprehensive income. Financial Instruments Derivative financial instruments are employed to manage risks associated with interest rate exposures and are not used for trading or speculative purposes. We recognize all derivative instruments in our consolidated balance sheets at fair value. Changes in the fair value of derivatives are recognized periodically either in earnings or in stockholders’ equity as a component of accu

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Acquisitions	4 . Acquisitions On January 14, 2019, we completed the acquisition of certain assets of PV Waggle LLC, which comprised a web-based adaptive learning solution providing Math and English Language Arts (“ELA”) instruction for students in grades 2-8 for a total purchase price of approximately $5.4 million. The transaction was accounted for under the acquisition method of accounting. Goodwill, other intangible assets and other liabilities recorded as part of the acquisition totaled approximately $0.9 million, $5.2 million and $0.7 million, respectively. The other intangible assets represent developed technology and were valued using a replacement cost approach. Pro forma financial information and measurement period adjustments were not material.

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2020
Discontinued Operations And Disposal Groups [Abstract]
Discontinued Operations	5 . On October 1, 2018, we completed the sale of all the assets, including intellectual property, used primarily in our Riverside clinical and standardized testing business (“Riverside Business”) for cash consideration received of $140.0 million and the purchaser’s assumption of all liabilities relating to the Riverside Business subject to specified exceptions. Net proceeds from the sale after the payment of transaction costs were approximately $135.0 million with a post-tax book gain on sale of approximately $30.5 million. The gain was recorded in the fourth quarter of 2018 as the transaction closed on October 1, 2018. The tax gain on the sale was offset by 2018 losses. The results of the Riverside Business were previously reported in our Education segment. In connection with the sale of the Riverside Business, we entered into a Transition Services Agreement with the purchaser whereby we performed certain support functions through September 30, 2019. Upon the signing of the asset purchase agreement on September 12, 2018, the Riverside Business qualified as a discontinued operation, and goodwill originally included in the Education reportable segment was transferred to the Riverside Business. The amount of transferred goodwill was $67.0 million and was determined using the relative fair value method. The relative fair value was determined based on the purchase price of the Riverside Business compared to the Education reportable segment fair value. The Education reportable segment fair value was based primarily on the market value of the overall Company at the date that the Riverside Business qualified as a discontinued operation. The allocation also required the assessment for impairment for each of the Riverside Business and Education reportable segment’s goodwill and indefinite-lived intangible assets carrying values. No impairment was deemed to exist. Selected financial information of the Riverside Business included in discontinued operations is as follows: For the Year Ended December 31, 2018 Net sales $ 56,562 Costs 37,714 Amortization 4,954 Earnings from discontinued operations before taxes 13,894 Income tax expense 1,061 Earnings from discontinued operations, net of tax $ 12,833

Balance Sheet Information

Balance Sheet Information	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Information	6 . Account Receivable Accounts receivable at December 31, 2020 and 2019 consisted of the following: 2020 2019 Accounts receivable $ 171,395 $ 204,119 Allowance for bad debt (3,989 ) (3,015 ) Reserve for book returns (14,574 ) (16,679 ) $ 152,832 $ 184,425 As of December 31, 2020 and 2019, one individual customer comprised more than 10% of our accounts receivable, net balance. Inventories Inventories at December 31, 2020 and 2019 consisted of the following: 2020 2019 Finished goods $ 155,759 $ 203,103 Raw materials 11,204 9,956 Inventories $ 166,963 $ 213,059 Property, Plant, and Equipment Balances of major classes of assets and accumulated depreciation and amortization at December 31, 2020 and 2019 were as follows: 2020 2019 Land and land improvements $ 4,939 $ 4,939 Building and building equipment 11,160 10,239 Machinery and equipment 14,985 12,970 Capitalized software and internal-use software 641,027 598,317 Leasehold improvements 24,266 22,974 Film and media 29,845 22,055 726,222 671,494 Less: Accumulated depreciation and amortization (633,020 ) (571,106 ) Property, plant, and equipment, net $ 93,202 $ 100,388 For the years ended December 31, 2020, 2019 and 2018, depreciation and amortization expense related to property, plant, and equipment were $64.7 million, $71.3 million and $81.2 million, respectively. Property, plant, and equipment at December 31, 2020 and 2019 included approximately $0.1 million and $0.3 million, respectively, acquired under finance lease agreements, of which the majority is included in machinery and equipment. The future minimum lease payments required under non-cancelable capital leases as of December 31, 2020 are $0.1 million Included within property, plant, and equipment on our consolidated balance sheets are film and media assets. Our film and media assets are comprised of the cost to develop our animated series Carmen Sandiego and other production series. These assets will be amortized proportionally to the revenues recognized relative to the total estimated revenue consistent with the guidance over episodic television series development. We recorded amortization expense of $14.0 million, $9.8 million and $6.1 million for the years ended December 31, 2020, 2019 and 2018, respectively, against this asset, which is included within cost of sales, excluding publishing rights and pre-publication amortization, in the statement of operations. Substantially all property, plant, and equipment are pledged as collateral under our term loan and revolving credit facility. Contract Assets, Contract Liabilities and Contract Costs Contract assets consist of unbilled amounts at the reporting date and are transferred to accounts receivable when the rights become unconditional. Contract assets are included in prepaid expenses and other assets on our consolidated balance sheets. Contract liabilities consist of deferred revenue (current and long-term). The following table presents changes in contract assets and contract liabilities during the year ended December 31, 2020: December 31, December 31, 2020 2019 $ Change % Change Contract assets $ 580 $ 109 $ 471 432.11 % Contract liabilities (deferred revenue) $ 905,284 $ 848,106 $ 57,178 6.74 % The $56.7 million increase in our net contract liabilities from December 31, 2019 to December 31, 2020 was primarily due to the non-satisfaction of performance obligations related to physical and digital products, and services during the period in excess of recognition from deferred revenue. During the years ended December 31, 2020, 2019 and 2018, we recognized the following net sales as a result of changes in the contract assets and contract liabilities balances: Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Net sales recognized in the period from: Amounts included in contract liabilities at the beginning of the period $ 295,675 $ 229,557 $ 220,769 As of December 31, 2020, the aggregate amount of the transaction price allocated to the remaining performance obligations, which includes deferred revenue and open orders, was $970.3 million, and we will recognize approximately 73% to net sales over the next 1 to 3 years. We capitalize incremental commissions paid to sales representatives for obtaining product sales as well as service contracts unless the capitalization and amortization of such costs are not expected to have a material impact on the financial statements. Applying the practical expedient within the accounting guidance, we recognize sales commission expense when incurred if the amortization period of the assets that we otherwise would have recognized is one year or less. We had deferred commissions in the amount of $30.7 million and $29.3 million at December 31, 2020 and 2019, respectively, and amortized $12.9 million, $13.2 million and $10.5 million during the years ended December 31, 2020, 2019 and 2018, respectively. The amortization is included in selling and administrative expenses. Costs to fulfill a contract are directly related to a contract that will be used to satisfy a performance obligation in the future and are expected to be recovered. These costs are amortized on a systematic basis that is consistent with the transfer to the customer of the goods or services to which the asset relates. Our assets associated with incremental costs to fulfill a contract were $14.7 million and $5.6 million at December 31, 2020 and 2019, respectively, and are included within prepaid expenses and other assets (current) and other assets (long term) on our consolidated balance sheet. We recorded amortization of $3.8 million and $4.6 million during the years ended December 31, 2020 and 2019, respectively. The amortization is included in cost of sales, excluding publishing rights and pre-publication amortization.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	7 . The change in the carrying amount of goodwill, which all relates to the Education segment, for the year ended December 31, 2020 is as follows: Balance at December 31, 2019 $ 716,977 Impairment (279,000) Balance at December 31, 2020 $ 437,977 In accordance with the provisions of the accounting standard for goodwill and other intangible assets, goodwill and certain indefinite-lived tradenames are not amortized but rather are assessed for impairment on an annual basis. Accumulated impairment losses on goodwill as of December 31, 2020 was $279.0 million. Refer to Note 2 for a discussion of the valuation of goodwill, indefinite-lived intangible assets and long-lived assets along with the triggering event which resulted in a goodwill impairment of $279.0 million during the year ended December 31, 2020. There was no impairment charge recorded in the years ended December 31, 2019 and 2018. Other intangible assets consisted of the following: December 31, 2020 December 31, 2019 Accumulated Accumulated Cost Amortization Total Cost Amortization Total Trademarks and tradenames: indefinite- Lived $ 161,000 $ — $ 161,000 $ 161,000 $ — $ 161,000 Trademarks and tradenames: definite- Lived 164,130 (53,610 ) 110,520 164,130 (38,948 ) 125,182 Publishing rights 1,180,000 (1,159,482 ) 20,518 1,180,000 (1,139,426 ) 40,574 Customer related and other 449,840 (313,294 ) 136,546 449,840 (302,371 ) 147,469 Other intangible assets, net $ 1,954,970 $ (1,526,386 ) $ 428,584 $ 1,954,970 $ (1,480,745 ) $ 474,225 During 2019, we acquired certain assets of PV Waggle LLC and recorded an intangible asset of $5.2 million. Refer to Note 4. Amortization expense for definite-lived intangible assets, publishing rights and customer related and other intangibles were $45.6 million, $51.9 million and $61.6 million for the years ended December 31, 2020, 2019 and 2018, respectively. Estimated aggregate amortization expense expected for each of the next five years related to intangibles subject to amortization is as follows: Trademarks Other and Publishing Intangible Tradenames Rights Assets 2021 14,408 11,642 10,333 2022 10,608 7,569 10,134 2023 6,808 1,307 9,954 2024 6,715 — 8,503 2025 6,437 8,315 Thereafter 65,544 — 89,307 $ 110,520 $ 20,518 $ 136,546

Debt

Debt	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt	8 . Our debt consisted of the following: December 31, December 31, 2020 2019 $380,000 term loan due November 22, 2024 interest payable quarterly (net of discount and issuance costs) $ 346,091 $ 361,294 $306,000 senior secured notes due February 15, 2025 interest payable semi-annually (net of discount and issuance costs) 297,601 295,893 643,692 657,187 Less: Current portion of long-term debt (19,000 ) (19,000 ) Total long-term debt, net of discount and issuance Costs $ 624,692 $ 638,187 Revolving credit facility $ — $ — Long-term debt repayments due in each of the next five years and thereafter is as follows: Year 2021 19,000 2022 19,000 2023 19,000 2024 304,000 2025 306,000 $ 667,000 Senior Secured Notes On November 22, 2019, we completed the sale of $306.0 million in aggregate principal amount of 9.0% Senior Secured Notes due 2025 (the “notes”) in a private placement to qualified institutional buyers under Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), and to persons outside the United States pursuant to Regulation S under the Securities Act. The notes mature on February 15, 2025 and bear interest at a rate of 9.0% per annum. Interest is payable semi-annually in arrears on February 15 and August 15 of each year, beginning on February 15, 2020. The notes were issued at a discount equal to 2.0% of the outstanding borrowing commitment. The transaction was accounted for under the guidance for debt modifications and extinguishments. We incurred approximately $5.4 million of third-party fees for the transaction, of which approximately $4.1 million were capitalized as deferred financing fees and approximately $1.3 million was recorded to expense and included in the selling and administrative line item in our consolidated statements of operations for the year ended December 31, 2019. We may redeem all or a portion of the notes at redemption prices as described in the notes. The notes do not require us to comply with financial maintenance covenants. We are currently required to meet certain incurrence based financial covenants as defined under our notes. The notes are subject to restrictions on our ability to incur additional indebtedness, issue certain preferred stock, redeem, purchase or retire subordinated debt, make certain investments, pay dividends or other amounts, enter into certain transactions with affiliates, merge or consolidate with another person, sell or otherwise dispose of all or substantially all of our assets, sell certain assets, including capital stock, designate our subsidiaries as unrestricted subsidiaries, redeem or repurchase capital stock or make other restricted payments, and incur certain liens. The notes are subject to customary events of default. If an event of default occurs and is continuing, the administrative agent may, or at the request of certain required lenders shall, accelerate the obligations outstanding under the notes. Term Loan Facility On November 22, 2019, we entered into a second amended and restated term loan credit agreement for an aggregate principal amount of $380.0 million (the “term loan facility”). The term loan facility is required to be repaid in quarterly installments of approximately $4.8 million with the balance being payable on the maturity date. The term loan facility matures on November 22, 2024 and the interest rate per annum is equal to, at the option of the Company, either (a) LIBOR plus a margin of 6.25% or (b) an alternate base rate plus a margin of 5.25%. As of December 31, 2020, the interest rate on the term loan facility was 7.25%. On July 27, 2017, the U.K. Financial Conduct Authority (the “FCA”) announced that it will no longer require banks to submit rates for the calculation of LIBOR after 2021. Our term loan facility provides that the administrative agent may determine that (i) adequate and reasonable means do not exist for ascertaining the LIBOR rate or (ii) the FCA or the government authority having jurisdiction over the administrative agent has made a public statement identifying a specific date after which the LIBOR rate shall no longer be used for determining interest rates for loans. If the administrative agent determines that (i) or (ii) above is unlikely to be temporary then the administrative agent and the Company will agree to transition to an alternate base rate or amend the term loan facility to establish an alternate rate of interest to LIBOR that gives due consideration to the then-prevailing market convention for determining a rate of interest for syndicated loans in the United States at such time. The term loan facility was issued at a discount equal to 4.0% of the outstanding borrowing commitment. The transaction was accounted for under the guidance for debt modifications and extinguishments. We incurred approximately $7.2 million of third-party fees for the transaction, of which approximately $2.9 million were capitalized as deferred financing fees and approximately $4.3 million was recorded to expense and included in the selling and administrative line item in our consolidated statements of operations for the year ended December 31, 2019. The term loan facility contains customary mandatory prepayment requirements, including with respect to excess cash flow, proceeds from certain asset sales or dispositions of property, and proceeds from certain incurrences of indebtedness. The term loan facility permits the Company to voluntarily prepay outstanding amounts at any time without premium or penalty, other than customary breakage costs with respect to LIBOR loans; provided, however, that any voluntary prepayment in connection with certain repricing transactions that occur before the date that is twelve months after the closing of the term loan facility shall be subject to a prepayment premium of 1.00% of the principal amount of the amounts prepaid. The term loan facility does not require us to comply with financial maintenance covenants. We are currently required to meet certain incurrence based financial covenants as defined under our term loan facility. The term loan facility is subject to usual and customary conditions, representations, warranties and covenants, including restrictions on additional indebtedness, liens, investments, mergers, acquisitions, asset dispositions, dividends to stockholders, repurchase or redemption of our stock, transactions with affiliates and other matters. The term loan facility is subject to customary events of default. If an event of default occurs and is continuing, the administrative agent may, or at the request of certain required lenders shall, accelerate the obligations outstanding under the term loan facility. We are subject to an excess cash flow provision under our term loan facility which is predicated upon our leverage ratio and cash flow. We were not required to make a payment under the excess cash flow provision in 2020 and 2019. On November 22, 2019, in connection with the notes and term loan facility described above, we paid off the remaining outstanding balance of our previous $800.0 million term loan facility. The transaction was accounted for under the guidance for debt modifications and extinguishments. We incurred a loss on extinguishment of debt of approximately $4.4 million related to the write off of the portion of the unamortized deferred financing fees and discount associated with the portion of the previous term loan accounted for as an extinguishment Interest Rate Hedging On August 17, 2015, we entered into interest rate derivative contracts with various financial institutions having an aggregate notional amount of $400.0 million to convert floating rate debt into fixed rate debt. We assessed at inception, and re-assess on an ongoing basis, whether the interest rate derivative contracts are highly effective in offsetting changes in the fair value of the hedged variable rate debt. The interest rate derivative contracts matured on July 22, 2020. These interest rate swaps were designated as cash flow hedges and qualified for hedge accounting under the accounting guidance related to derivatives and hedging. Accordingly, we recorded an unrealized loss of $3.4 million and an unrealized gain of $3.5 million In connection with the term loan facility on November 22, 2019, we incurred a change in the mix of floating rate debt versus fixed rate debt. As a result, the aggregate notional of our active interest rate derivative contracts designated as cash flow hedges exceeded the outstanding floating rate debt notional by approximately $29.5 million. To accommodate for this notional shortfall, we partially de-designated one of our active interest rate derivative contracts. This involved splitting the notional amount with one portion remaining designated under cash flow hedge accounting, and the remaining portion, with a $29.5 million notional amount, left undesignated. There were no changes made to the interest rate derivative contracts from an economic perspective; the notional split is accounting in nature only. Beginning on November 22, 2019, the fair value changes on the undesignated portion of the swap flow through earnings, as opposed to being deferred as unrealized gains or losses in other comprehensive income (loss). The impact of this change was less than $0.1 Revolving Credit Facility On November 22, 2019, we entered into a second amended and restated revolving credit agreement that provides borrowing availability in an amount equal to the lesser of either $250.0 million or a borrowing base that is computed monthly or weekly and comprised of the Borrowers’ and the Guarantors’ (as such terms are defined below) eligible inventory and receivables (the “revolving credit facility”). The revolving credit facility includes a letter of credit subfacility of $50.0 million, a swingline subfacility of $20.0 million and the option to expand the facility by up to $100.0 million in the aggregate under certain specified conditions. The revolving credit facility may be prepaid, in whole or in part, at any time, without premium. The transaction was accounted for under the accounting guidance for modifications to or exchanges of revolving debt arrangements. We incurred approximately $1.1 million of creditor and third-party fees which were capitalized as deferred financing fees. The revolving credit facility requires the Company to maintain a minimum fixed charge coverage ratio of 1.0 to 1.0 on a trailing four-quarter basis only during certain periods commencing when excess availability under the revolving credit facility is less than certain limits prescribed by the terms of the revolving credit facility. The revolving credit facility is subject to usual and customary conditions, representations, warranties and covenants, including restrictions on additional indebtedness, liens, investments, mergers, acquisitions, asset dispositions, dividends to stockholders, repurchase or redemption of our stock, transactions with affiliates and other matters. The revolving credit facility is subject to customary events of default. If an event of default occurs and is continuing, the administrative agent may, or at the request of certain required lenders shall, accelerate the obligations outstanding under the revolving credit facility. As of December 31, 2020, the minimum fixed charge coverage ratio covenant under our revolving credit facility was not applicable, due to our level of borrowing availability. The minimum fixed charge coverage ratio, which is only tested in limited situations, is 1.0 to 1.0 through the end of the facility. Guarantees Under each of the notes, the term loan facility and the revolving credit facility, Houghton Mifflin Harcourt Publishers Inc., Houghton Mifflin Harcourt Publishing Company and HMH Publishers LLC are the borrowers (collectively, the “Borrowers”), and Citibank, N.A. acts as both the administrative agent and the collateral agent. The obligations under the notes, the term loan facility and the revolving credit facility are guaranteed by the Company and each of its direct and indirect for-profit domestic subsidiaries (other than the Borrowers) (collectively, the “Guarantors”) and are secured by all capital stock and other equity interests of the Borrowers and the Guarantors and substantially all of the other tangible and intangible assets of the Borrowers and the Guarantors, including, without limitation, receivables, inventory, equipment, contract rights, securities, patents, trademarks, other intellectual property, cash, bank accounts and securities accounts and owned real estate. The revolving credit facility is secured by first priority liens on receivables, inventory, deposit accounts, securities accounts, instruments, chattel paper and other assets related to the foregoing (the “Revolving First Lien Collateral”), and second priority liens on the collateral which secures the term loan facility on a first priority basis. The term loan facility is secured by first priority liens on the capital stock and other equity interests of the Borrowers and the Guarantors, equipment, owned real estate, trademarks and other intellectual property, general intangibles that are not Revolving First Lien Collateral and other assets related to the foregoing, and second priority liens on the Revolving First Lien Collateral.

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	9 . Leases We lease property and equipment under finance and operating leases. We have operating leases for various office space and facilities, warehouse equipment, automobile fleet and office equipment that expire at various dates through 2033. For leases with terms greater than 12 months, we record the related asset and obligation at the present value of lease payments over the lease term. Many of our leases include rental escalation clauses, renewal options and/or termination options that are factored into our determination of lease payments when appropriate. For leases beginning in 2019 and later, we account for lease components (e.g., fixed payments including rent, real estate taxes and insurance costs) as combined with the non-lease components (e.g., common-area maintenance costs). Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. We sublease certain real estate office space to third parties. Our sublease portfolio consists of operating leases. When available, we use the rate implicit in the lease to discount lease payments to present value; however, most of our leases do not provide a readily determinable implicit rate. Therefore, we must estimate our incremental borrowing rate to discount the lease payments based on information available at lease commencement. We give consideration to our recent debt issuances as well as publicly available data for instruments with similar characteristics when calculating our incremental borrowing rates. Lease Position as of December 31, 20 20 The table below presents the lease assets and liabilities recorded on the balance sheet. Leases Classification December 31, 2020 December 31, 2019 Assets Operating lease assets Operating lease assets $ 126,850 $ 132,247 Total leased assets $ 126,850 $ 132,247 Liabilities Current Operating Operating lease liabilities $ 9,669 $ 8,685 Noncurrent Operating Operating lease liabilities 132,014 134,994 Total lease liabilities $ 141,683 $ 143,679 Weighted average remaining lease term Operating leases 8.2 Years 9.6 Years Weighted average discount rate Operating leases (1) 12.56 % 12.46 % (1) Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019. Lease costs Operating lease cost and sublease income totaled $34.9 million and $2.1 million and $39.9 million and $2.3 million for the years ended December 31, 2020 and 2019, respectively. The net lease cost of $32.8 million and $37.6 million for years ended December 31, 2020 and 2019, respectively, is included in the selling and administrative line item in our consolidated statements of operations. Operating lease cost includes short term leases and variable lease costs, which are not material. Undiscounted Cash Flows The table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the operating lease liabilities recorded on the balance sheet. Operating Maturity of Lease Liabilities Leases 2021 24,143 2022 25,395 2023 27,838 2024 29,034 2025 28,370 Thereafter 110,993 Total lease payments $ 245,773 Less: interest (104,090 ) Present value of lease liabilities $ 141,683 During the third quarter of 2019, we executed a lease agreement on new office space in Portsmouth, New Hampshire. We plan to relocate our employees from the existing location in Portsmouth, New Hampshire to this new office space upon the completion of the building. The lease term specified in the agreement is 10 years with an option to renew for an additional five years. Our estimated fixed lease payments over the 10 year initial lease term is $ 9.8 million. We currently expect to relocate to the space in the second quarter of 2021, but this timing as well as when we are required to begin making payments and recognize rental and other expenses under the new lease, is dependent on when the space is available for use. Other Information The table below presents supplemental cash flow information related to leases during the years ended December 31, 2020 and 2019. Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases – 2020 $ 28,639 Operating cash flows for operating leases – 2019 $ 31,245

Restructuring, Severance and Ot

Restructuring, Severance and Other Charges	12 Months Ended
	Dec. 31, 2020
Restructuring And Related Activities [Abstract]
Restructuring, Severance and Other Charges	10 . 2020 Restructuring Plan On September 4, 2020, we finalized a voluntary retirement incentive program, which was offered to On September 30, 2020, we undertook a restructuring program, including a reduction in force, as part of the ongoing assessment of our cost structure amid the COVID-19 pandemic and in line with our strategic transformation plan. The reduction in force resulted in a 22% reduction in our workforce, including positions eliminated as part of the voluntary retirement incentive program mentioned above, and net of newly created positions to support our digital first operations. The reduction in force will result in the departure of approximately 525 employees and was completed in October 2020. Each of the employees received or will receive separation payments in accordance with our severance policy. The total one-time, non-recurring cost incurred in connection with the restructuring program, inclusive of the voluntary retirement incentive program, (collectively the “2020 Restructuring Plan”) all of which represents cash expenditures, is approximately $33.6 million. The following table provides a summary of our total costs associated with the 2020 Restructuring Plan, included in the restructuring/severance and other charges line item within our consolidated statements of operations, for the year ended December 31, 2020, by major type of cost: Year Ended Total Amount December 31, Incurred Type of Cost 2020 to Date Restructuring charges: (1) Severance and termination benefits $ 33,643 $ 33,643 $ 33,643 $ 33,643 (1) All restructuring charges are included within Corporate and Other. Our restructuring liabilities are comprised of accruals for severance and termination benefits. The following is a rollforward of our liabilities associated with the 2020 Restructuring Plan: 2020 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2019 Charges payments 2020 Severance and termination benefits $ — $ 33,643 $ (14,332) $ 19,311 $ — $ 33,643 $ (14,332) $ 19,311 2019 Restructuring Plan On October 15, 2019, our Board of Directors approved changes connected with our ongoing strategic transformation to simplify our business model and accelerate growth. This includes new product development and go-to-market capabilities, as well as the streamlining of operations company-wide for greater efficiency. These actions (the “2019 Restructuring Plan”) resulted in the net elimination of approximately 10% of our workforce, after taking into account new strategy-aligned positions that are expected to be added, and additional operating and capitalized cost reductions, including an approximately 20% reduction in previously planned content development expenditures over the next three years. These steps are intended to further simplify our business model while delivering increased value to customers, teachers and students. The workforce reductions were completed in the first quarter of 2020. After considering additional headcount actions, implementation of the planned actions resulted in total charges of $15.8 million which was recorded in the fourth quarter of 2019. With respect to each major type of cost associated with such activities, substantially all costs were severance and other termination benefit costs and will result in cash expenditures. Further, as part of such strategic transformation plan, we recorded an incremental $9.8 million inventory obsolescence charge which is recorded in cost of sales in the statement of operations. The following tables provide a summary of our total costs associated with the 2019 Restructuring Plan, included in the restructuring line item within our consolidated statements of operations, for the year ended December 31, 2019, by major type of cost: Year Ended Total Amount December 31, Incurred Type of Cost 2019 to Date Restructuring charges: (1) Severance and termination benefits $ 15,820 $ 15,820 $ 15,820 $ 15,820 (1) All restructuring charges are included within Corporate and Other. Our restructuring liabilities are primarily comprised of accruals for severance and termination benefits. The following is a rollforward of our liabilities associated with the 2019 Restructuring Plan: 2020 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2019 Charges payments 2020 Severance and termination benefits $ 11,649 $ — $ (11,370 ) $ 279 $ 11,649 $ — $ (11,370 ) $ 279 2019 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2018 Charges payments 2019 Severance and termination benefits $ — $ 15,820 $ (4,171 ) $ 11,649 $ — $ 15,820 $ (4,171 ) $ 11,649 Severance and Other Charges 2020 Exclusive of the 2020 Restructuring Plan and the 2019 Restructuring Plan, during the year ended December 31, 2020, $0.8 million of severance payments were made to employees whose employment ended in 2019 and prior years. A summary of the significant components of the severance costs, which are not allocated to our segments and instead are included in the Corporate and Other category, is as follows: 2020 Severance/ other accruals at December 2019 Severance/ other expense Cash payments Severance/ other accruals at December 31, 2020 Severance costs $ 758 $ — $ (758 ) $ — $ 758 $ — $ (758 ) $ — 2019 Exclusive of the 2019 Restructuring Plan, during the year ended December 31, 2019, $3.2 million of severance payments were made to employees whose employment ended in 2019 and prior years, and we recorded an expense in the amount of $2.5 million to reflect costs for severance. We also recorded an expense in the amount of $3.4 million for real estate consolidation costs, which is reflected as a reduction in operating lease assets in our consolidated balance sheet as of December 31, 2019. 2019 Severance/ Severance/ other other accruals at Severance/ accruals at December 31, other Cash December 31, 2018 expense payments 2019 Severance costs $ 1,420 $ 2,534 $ (3,196 ) $ 758 Other accruals 270 (1) — — — $ 1,690 $ 2,534 $ (3,196 ) $ 758 (1) 2018 During the year ended December 31, 2018, $5.7 million of severance payments were made to employees whose employment ended in 2018 and prior years and $1.0 million of net payments were made for office space no longer utilized by the Company as a result of prior savings initiatives. Further, we recorded an expense in the amount of $6.8 million to reflect costs for severance, which have been fully paid. A summary of the significant components of the severance/restructuring and other charges, which are not allocated to our segments and included in Corporate and Other, is as follows: 2018 Severance/ Severance/ other other accruals at Severance/ accruals at December 31, other Cash December 31, 2017 expense payments 2018 Severance costs $ 341 $ 6,821 $ (5,742 ) $ 1,420 Other accruals 1,299 — (1,029 ) 270 $ 1,640 $ 6,821 $ (6,771 ) $ 1,690 The current portion of the severance and other charges was $19.6 million and $12.4 million (inclusive of the 2019 Restructuring Plan and 2020 Restructuring Plan) as of December 31, 2020 and 2019, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	11 . The components of loss before taxes by jurisdiction are as follows: For For For the Year the Year the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 U.S. $ (494,456 ) $ (213,541 ) $ (134,884 ) Foreign 2,214 3,909 3,024 Loss before taxes $ (492,242 ) $ (209,632 ) $ (131,860 ) Total income taxes by jurisdiction are as follows: For For For the Year the Year the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Income tax expense (benefit) U.S. $ (12,691 ) $ 4,273 $ 3,701 Foreign 287 (72 ) 1,896 $ (12,404 ) $ 4,201 $ 5,597 Significant components of the (benefit) expense for income taxes attributable to loss from continuing operations consist of the following: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Current Foreign $ 182 $ (730 ) $ 1,562 U.S.—Federal — 0 (63 ) U.S.—State and other 1,769 396 (1,042 ) Total current 1,951 (334 ) 457 Deferred Foreign 105 658 334 U.S.—Federal (5,505 ) 1,908 2,329 U.S.—State and other (8,955 ) 1,969 2,477 Total deferred (14,355 ) 4,535 5,140 Income tax (benefit) expense $ (12,404 ) $ 4,201 $ 5,597 The reconciliation of the income tax rate computed at the statutory tax rate to the reported income tax expense (benefit) attributable to continuing operations is as follows: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Statutory rate 21.0 % 21.0 % 21.0 % Permanent items (0.9 ) (3.6 ) (2.6 ) Foreign rate differential — — (0.1 ) State and local taxes 2.0 (7.9 ) 6.8 Cancellation of debt income — (1.3 ) — Increase in valuation allowance (15.5 ) (10.0 ) (26.6 ) Tax credits (0.2 ) (0.2 ) (2.7 ) Goodwill impairment (3.9 ) — — Effective tax rate 2.5 % (2.0 )% (4.2 )% The significant components of the net deferred tax assets and liabilities are shown in the following table: 2020 2019 Tax assets related to Net operating loss and other carryforwards $ 326,504 $ 272,378 Returns reserve/inventory expense 39,095 41,824 Pension benefits 6,879 6,624 Postretirement benefits 4,480 4,475 Deferred interest (1) 226,227 259,375 Deferred revenue 141,775 113,029 Stock-based compensation 2,806 3,298 Deferred compensation 6,525 6,152 Research and development 12,435 10,302 Operating lease liabilities 33,963 35,890 Other, net 8,263 6,769 Valuation allowance (662,569 ) (583,505 ) $ 146,383 $ 176,611 2020 2019 Tax liabilities related to Indefinite-lived intangible assets (53,400 ) (89,879 ) Definite-lived intangible assets (21,578 ) (25,503 ) Depreciation and amortization expense (45,279 ) (48,984 ) Operating lease assets (30,245 ) (32,887 ) Other, net (9,877 ) (7,709 ) (160,379 ) (204,962 ) Net deferred tax liabilities $ (13,996 ) $ (28,351 ) ( 1 ) The deferred interest tax asset represents disallowed interest deductions under Section 163(j) (Limitation on Deduction for interest on Certain Indebtedness) of the Internal Revenue Code of 1986, as amended (“IRC”) for the current and prior years. At December 31, 2020 and 2019, we had gross deferred interest deductions totaling $900.2 million and $984.5 million, respectively. The disallowed interest is able to be carried forward indefinitely and utilized in future years pursuant to IRC Section 163(j). A full valuation allowance has been provided against deferred tax assets, excluding $2.4 million of foreign deferred tax assets which are expected to be realized, net of deferred tax liabilities resulting from indefinite-lived intangibles. The net deferred tax liability balance is stated at prevailing statutory income tax rates. Deferred tax assets and liabilities are reflected on our consolidated balance sheets as follows: 2020 2019 Non-current deferred tax assets $ 2,415 $ 2,520 Non-current deferred tax liabilities (16,411 ) (30,871 ) $ (13,996 ) $ (28,351 ) A reconciliation of the gross amount of unrecognized tax benefits, excluding accrued interest and penalties, is as follows: Balance at December 31, 2017 $ 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2018 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2019 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2020 $ 15,680 We are currently open for audit under the statute of limitation for Federal, state and foreign jurisdictions for years 2017 to 2020. However, carryforward attributes from prior years may still be adjusted upon examination by tax authorities if they are used in a future period. We report penalties and tax-related interest expense on unrecognized tax benefits as a component of the provision for income taxes in the accompanying consolidated statement of operations. At December 31, 2020 and 2019, accrued interest and penalties in the accompanying consolidated balance sheet and interest and penalties included in the provision for income taxes for the years ended December 31, 2020, 2019 and 2018 were immaterial. As of December 31, 2020, we have approximately $1,058.8 million of Federal tax loss carryforwards, of which $612.5 million will Under Section 382 of the IRC, substantial changes in the Company’s ownership may limit the amount of net operating loss and Section 163(j) carryforwards that could be utilized annually in the future to offset taxable income. Specifically, this limitation may arise in the event of a cumulative change in ownership of the Company of more than 50% within a three-year period. Any such annual limitation may significantly reduce the utilization of net operating loss carryforwards before they expire. The Company performed an analysis through December 31, 2020, and determined any potential ownership change under Section 382 during the year would not have a material impact on the future utilization of U.S. net operating losses and tax credits. However, future transactions in the Company’s common stock could trigger an ownership change for purposes of Section 382, which could limit the amount of net operating loss carryforwards and other attributes that could be utilized annually in the future to offset taxable income, if any. Any such limitation, whether as the result of sales of common stock by our existing stockholders or sales of common stock by the Company, could have a material adverse effect on results of operations in future years . U.S. income taxes on the undistributed earnings of the Company’s non-U.S. subsidiaries have not been provided for as the Company currently plans to indefinitely reinvest these amounts and has the ability to do so. There are no cumulative undistributed and untaxed foreign earnings at December 31, 2020 and 2019. Based on our assessment of historical pre-tax losses and the fact that we did not anticipate sufficient future taxable income in the near term to assure utilization of certain deferred tax assets, the Company recorded a valuation allowance at December 31, 2020 and 2019 of $662.6 million and $583.5 million, respectively. We have increased our valuation allowance by $79.1 million in 2020 with $76.7 million as a component of operations and $2.4 million as a component of other comprehensive income.

Retirement and Postretirement B

Retirement and Postretirement Benefit Plans	12 Months Ended
	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
Retirement and Postretirement Benefit Plans	1 2 . Retirement Plan We have a noncontributory, qualified defined benefit pension plan (the “Retirement Plan”), which covers certain employees. The Retirement Plan is a cash balance plan, which accrues benefits based on pay, length of service, and interest. The funding policy is to contribute amounts subject to minimum funding standards set forth by the Employee Retirement Income Security Act of 1974 and the IRC. The Retirement Plan’s assets consist principally of common stocks, fixed income securities, investments in registered investment companies, and cash and cash equivalents. We also have a nonqualified defined benefit plan, or nonqualified plan, that previously covered employees who earned over the qualified pay limit as determined by the Internal Revenue Service. The nonqualified plan accrues benefits for the participants based on the cash balance plan calculation. The nonqualified plan is not funded. We use a December 31 date to measure the pension and postretirement liabilities. In 2007, both the qualified and nonqualified pension plans eliminated participation in the plans for new employees hired after October 31, 2007. We recognize the funded status of defined benefit pension and other postretirement plans as an asset or liability in the balance sheet and are required to recognize actuarial gains and losses and prior service costs and credits in other comprehensive income and subsequently amortize those items in the statement of operations. The following table summarizes the Accumulated Benefit Obligations (“ABO”), the change in Projected Benefit Obligation (“PBO”), and the funded status of our plans as of and for the financial statement period ended December 31, 2020 and 2019: 2020 2019 ABO at end of period $ 179,408 $ 169,364 Change in PBO PBO at beginning of period $ 169,364 $ 162,096 Interest cost on PBO 4,388 6,045 Plan settlements (4,990 ) — Actuarial loss (gain) 18,447 12,507 Benefits paid (7,801 ) (11,284 ) PBO at end of period $ 179,408 $ 169,364 Change in plan assets Fair market value at beginning of period $ 145,716 $ 132,776 Actual return 16,060 22,955 Company contribution 4,769 1,269 Plan settlements (4,990 ) — Benefits paid (7,801 ) (11,284 ) Fair market value at end of period $ 153,754 $ 145,716 Unfunded status $ (25,654 ) $ (23,648 ) Amounts recognized in the consolidated balance sheets at December 31, 2020 and 2019 consist of: 2020 2019 Current liabilities $ (1,593 ) $ — Noncurrent liabilities (24,061 ) (23,648 ) Net amount recognized $ (25,654 ) $ (23,648 ) Additional year-end information for pension plans with ABO in excess of plan assets at December 31, 2020 and 2019 consist of: 2020 2019 PBO $ 179,408 $ 169,364 ABO 179,408 169,364 Fair value of plan assets 153,754 145,716 Weighted average assumptions used to determine the benefit obligations (both PBO and ABO) at December 31, 2020 and 2019 are: 2020 2019 Discount rate 2.2 % 3.1 % Increase in future compensation N/A N/A Net periodic pension (income) cost includes the following components: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Interest cost on projected benefit obligation $ 4,388 $ 6,045 $ 5,300 Expected return on plan assets (7,419 ) (7,659 ) (7,985 ) Amortization of net loss 2,325 1,028 1,420 Settlement loss recognized 1,100 — — Net pension (income) expense recognized for the period $ 394 $ (586 ) $ (1,265 ) Significant actuarial assumptions used to determine net periodic pension cost at December 31, 2020, 2019 and 2018 are: 2020 2019 2018 Discount rate 3.1 % 4.2 % 3.6 % Increase in future compensation N/A N/A N/A Expected long-term rate of return on assets 5.5 % 5.5 % 5.5 % Assumptions on Expected Long-Term Rate of Return as Investment Strategies We employ a building block approach in determining the long-term rate of return for plan assets. Historical markets are studied and long-term relationships between equities and fixed income are preserved congruent with the widely accepted capital market principle that assets with higher volatility generate a greater return over the long run. Current market factors such as inflation and interest rates are evaluated before long-term capital market assumptions are determined. The long-term portfolio return is established via a building block approach and proper consideration of diversification and rebalancing. Peer data and historical returns are reviewed for reasonability and appropriateness. We regularly review the actual asset allocation and periodically rebalances investments to a targeted allocation when appropriate. The current targeted asset allocation is 34% with equity managers, 56% with fixed income managers, 5% with real-estate investment trust managers and 5% with hedge fund managers. For 2021, we will use a 5.50% long-term rate of return for the Retirement Plan. We will continue to evaluate the expected rate of return assumption, at least annually, and will adjust as necessary. Plan Assets Plan assets for the U.S. tax qualified plans consist of a diversified portfolio of fixed income securities, equity securities, real estate, and cash equivalents. Plan assets do not include any of our securities. The U.S. pension plan assets are invested in a variety of funds within a Collective Trust (“Trust”). The Trust is a group trust designed to permit qualified trusts to comingle their assets for investment purposes on a tax-exempt basis. Investment Policy and Investment Targets The tax qualified plans consist of the U.S. pension plan and the U.K. pension scheme (prior to May 28, 2014). We fund amounts for our qualified pension plans at least sufficient to meet minimum requirements of local benefit and tax laws. The investment objectives of our pension plan asset investments are to provide long-term total growth and return, which includes capital appreciation and current income. The nonqualified noncontributory defined benefit pension plan is generally not funded. Assets were invested among several asset classes. The percentage of assets invested in each asset class at December 31, 2020 and 2019 is shown below. 2020 2019 Percentage Percentage in Each in Each Asset Class Asset Class Asset Class Equity 33.5 % 32.6 % Fixed income 52.7 54.5 Real estate investment trust 7.0 8.0 Other 6.8 4.9 100.0 % 100.0 % Fair Value Measurements The fair value of our pension plan assets by asset category at December 31 were as follows: December 31, Not subject 2020 to leveling (1) Cash and cash equivalents $ 1,914 $ 1,914 Equity securities U.S. equity 27,765 27,765 Non-US equity 15,544 15,544 Emerging markets equity 8,259 8,259 Fixed income Government bonds 28,855 28,855 Corporate bonds 46,228 46,228 Mortgage-backed securities 9 9 Asset-backed securities 810 810 Commercial mortgage-backed securities 604 604 International fixed income 4,485 4,485 Alternatives Real estate 10,689 10,689 Hedge funds 8,228 8,228 Other 364 364 $ 153,754 $ 153,754 (1) Investments that are valued using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. December 31, Not subject 2019 to leveling (1) Cash and cash equivalents $ 1,413 $ 1,413 Equity securities U.S. equity 28,993 28,993 Non-US equity 12,474 12,474 Emerging markets equity 5,537 5,537 Fixed income Government bonds 20,316 20,316 Corporate bonds 37,925 37,925 Mortgage-backed securities 7,943 7,943 Asset-backed securities 3,255 3,255 Commercial mortgage-backed securities 1,930 1,930 International fixed income 5,741 5,741 Alternatives Real estate 11,609 11,609 Hedge funds 7,043 7,043 Other 1,537 1,537 $ 145,716 $ 145,716 We recognize that risk and volatility are present to some degree with all types of investments. However, high levels of risk are minimized through diversification by asset class, and by style of each fund. Estimated Future Benefit Payments The following benefit payments are expected to be paid. Fiscal Year Ended Pension 2021 $ 14,030 2022 12,817 2023 12,581 2024 12,789 2025 13,356 2026–2030 61,944 Expected Contributions We expect to contribute $3.3 million in 2021. Postretirement Benefit Plan We also provide postretirement medical benefits to retired full-time, nonunion employees hired before April 1, 1992, who have provided a minimum of five years of service and attained age 55. The following table summarizes the Accumulated Postretirement Benefit Obligation (“APBO”), the changes in plan assets, and the funded status of our plan as of and for the financial statement periods ended December 31, 2020 and 2019. 2020 2019 Change in APBO APBO at beginning of period $ 16,684 $ 15,812 Service cost (benefits earned during the period) 67 58 Interest cost on APBO 426 582 Employee contributions 184 66 Actuarial loss (gain) 2,857 1,878 Benefits paid (2,097 ) (1,712 ) APBO at end of period $ 18,121 $ 16,684 Change in plan assets Fair market value at beginning of period $ — $ — Company contributions 1,913 1,646 Employee contributions 184 66 Benefits paid (2,097 ) (1,712 ) Fair market value at end of period $ — $ — Unfunded status $ (18,121 ) $ (16,684 ) Amounts for postretirement benefits accrued in the consolidated balance sheets at December 31, 2020 and 2019 consist of: 2020 2019 Current liabilities $ (1,555 ) $ (1,571 ) Noncurrent liabilities (16,566 ) (15,113 ) Net amount recognized $ (18,121 ) $ (16,684 ) Amounts not yet reflected in net periodic benefit cost and recognized in accumulated other comprehensive (loss) income at December 31, 2020 and 2019 consist of: 2020 2019 Net (loss) gain $ (1,050 ) $ 1,771 Prior service cost (384 ) (426 ) Accumulated other comprehensive (loss) income $ (1,434 ) $ 1,345 Weighted average actuarial assumptions used to determine APBO at year-end December 31, 2020 and 2019 are: 2020 2019 Discount rate 2.2 % 3.1 % Health care cost trend rate assumed for next year 5.5 % 5.8 % Rate to which the cost trend rate is assumed to decline (ultimate trend rate) 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2038 2038 Net periodic postretirement benefit cost included the following components: 2020 2019 2018 Service cost $ 67 $ 58 $ 128 Interest cost on APBO 426 582 672 Amortization of unrecognized prior service cost 42 42 (690 ) Amortization of net (gain) loss (7 ) (164 ) — Net periodic postretirement benefit expense $ 528 $ 518 $ 110 Significant actuarial assumptions used to determine postretirement benefit cost at December 31, 2020, 2019 and 2018 are: 2020 2019 2018 Discount rate 3.1 % 4.2 % 3.6 % Health care cost trend rate assumed for next year 5.8 % 6.1 % 6.3 % Rate to which the cost trend rate is assumed to decline (ultimate trend rate) 4.5 % 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2038 2038 2038 Assumed health care trend rates have a significant effect on the amounts reported for the health care plans. A one-percentage-point change in assumed health care cost trend rates would have the following effects on the expense recorded in 2020 and 2019 for the postretirement medical plan: 2020 2019 One-percentage-point increase Effect on total of service and interest cost components $ 2 $ 8 Effect on postretirement benefit obligation 87 85 One-percentage-point decrease Effect on total of service and interest cost components (2 ) (7 ) Effect on postretirement benefit obligation (77 ) (76 ) The following table presents the change in other comprehensive loss for the year ended December 31, 2020 related to our pension and postretirement obligations. Pension Postretirement Plans Benefit Plan Total Sources of change in accumulated other comprehensive loss Net loss arising during the period $ (9,807 ) $ (2,814 ) $ (12,621 ) Amortization of prior service credit — 42 42 Amortization of net gain (loss) 3,377 (7 ) 3,370 Total accumulated other comprehensive loss recognized during the period $ (6,430 ) $ (2,779 ) $ (9,209 ) Estimated amounts that will be amortized from accumulated other comprehensive income (loss) over the next fiscal year. Pension Postretirement Plans Benefit Plan Prior service credit (cost) $ — $ (42 ) Net gain (loss) (3,389 ) — $ (3,389 ) $ (42 ) Amounts not yet reflected in net periodic benefit cost for pension plans and postretirement plan and recognized in accumulated other comprehensive income at December 31, 2020 and 2019 consist of: 2020 2019 Net actuarial loss $ (44,219 ) $ (35,010 ) Accumulated other comprehensive loss $ (44,219 ) $ (35,010 ) Estimated Future Benefit Payments The following benefit payments, which reflect expected future service, are expected to be paid: Postretirement Fiscal Year Ended Benefit Plan 2021 $ 1,555 2022 1,488 2023 1,437 2024 1,389 2025 1,320 2026-2030 5,686 Expected Contribution We expect to contribute approximately $1.6 million in 2021. Defined Contribution Retirement Plan We maintain a defined contribution retirement plan, the Houghton Mifflin 401(k) Savings Plan, which conforms to Section 401(k) of the IRC and covers substantially all of our eligible employees. Participants may elect to contribute up to 50.0% of their compensation subject to an annual limit. We provide a matching contribution in amounts up to 3.0% of employee contributions. The 401(k) contribution expense amounted to $6.8 million, $7.4 million and $7.6 million for the years ended December 31, 2020, 2019 and 2018, respectively. We did not make any additional discretionary contributions in 2020, 2019 and 2018.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	1 3 . Total compensation expense related to grants of stock options, restricted stock units, and purchases under the employee stock purchase plan recorded in the years ended December 31, 2020, 2019 and 2018 was approximately $11.6 million, $14.0 million and $13.3 million, respectively, and is included in selling and administrative expense. 2015 Omnibus Incentive Plan Our Board of Directors adopted the 2015 Omnibus Incentive Plan (“Plan”) in February 2015, which became effective on May 19, 2015 following stockholder approval. The Plan initially provided to grant up to an aggregate of 4,000,000 shares of our common stock plus 2,615,476 shares of our common stock that were reserved for issuance under the 2012 Management Incentive Plan (“2012 MIP”) as of May 19, 2015 but were not issuable pursuant to any outstanding awards. There were 10,604,071 additional shares underlying outstanding awards under the 2012 MIP as of May 19, 2015 that could have otherwise become available again for grants under the 2012 MIP in the future (by potential forfeiture, withholding or otherwise) which will instead become reserved for issuance under the Plan in the event such shares become available for future grants. On December 13, 2019, our Board of Directors approved an amendment to the Plan to allow employees to have the share withholding increased from the minimum statutory rate to a higher rate, not to exceed the maximum statutory rate. On May 19, 2020, our shareholders approved an amended and restated Plan which increased the authorization of the number of shares available for grant under the Plan by 3,630,000 shares of our common stock. Our Compensation Committee may grant awards of nonqualified stock options, incentive (qualified) stock options or cash, stock appreciation rights, restricted stock awards, restricted stock units, performance compensation awards, other stock-based awards or any combination of the foregoing. Certain employees, directors, officers, consultants or advisors who have been selected by the Compensation Committee and who enter into an award agreement with respect to an award granted to them under the Plan are eligible for awards under the 2015 Omnibus Incentive Plan. The stock option awards will be granted at a strike price equal to or greater than the fair value per share of common stock as of the date of grant. The stock related to award forfeitures and stock withheld to cover tax withholding requirements upon vesting of restricted stock units remains outstanding and may be reallocated to new recipients. The purpose of the Plan is to help us attract and retain key personnel by providing them the opportunity to acquire an equity interest in our Company. As of May 19, 2015, there were 6,615,476 shares authorized and available for issuance under the Plan plus any amount that could have otherwise become available again for grants under the 2012 MIP in the future by forfeiture, withholding or otherwise. As of December 31, 2020, there were 6,996,290 shares authorized and available for future issuance under the Plan. The vesting terms for equity awards generally range from 1 to 4 years over equal annual installments and generally expire seven years after the date of grant. Stock Options The following table summarizes option activity for certain employees in our stock options: Weighted Number of Average Shares Exercise Price Balance at December 31, 2019 2,765,826 $ 13.10 Forfeited (868,614 ) 13.40 Balance at December 31, 2020 1,897,212 $ 12.95 Vested and expected to vest at December 31, 2020 1,883,100 $ 12.97 Exercisable at December 31, 2020 1,521,524 $ 13.65 As of December 31, 2020, the range of exercise prices is $5.25 to $22.80 with a weighted average remaining contractual life of 3.3 years for options outstanding. The weighted average remaining contractual life for options vested and expected to vest and exercisable was 3.3 years and 3.1 years, respectively. The intrinsic value of a stock option is the amount by which the current market value of the underlying stock exceeds the exercise price of the option as of the balance sheet date. The intrinsic value of options outstanding, options vested and expected to vest, and options exercisable was zero at December 31, 2020. The intrinsic value of options outstanding, options vested and expected to vest, and options exercisable was $0.1 million, $0.1 million and zero at December 31, 2019, respectively. We estimate the fair value of stock options using the Black-Scholes valuation model. Key input assumptions used to estimate the fair value of stock options include the exercise price of the award, the expected volatility of our stock over the option’s expected term, the risk-free interest rate over the option’s expected term, and our expected annual dividend yield. The fair value of each option granted was estimated on the grant date using the Black-Scholes valuation model with the following assumptions: For the Year Ended December 31, 2018 Expected term (years) (a) 4.75 Expected dividend yield 0.00% Expected volatility (b) 35.30% Risk-free interest rate (c) 2.84% (a) The expected term is the number of years that we estimate that options will be outstanding prior to exercise. During 2018, we have used the simplified method for estimating the expected term as we do not have sufficient stock option exercise experience to support a reasonable estimate of the expected term. The simplified method represents the best estimate of the expected term. (b) During 2018, we estimated volatility for options granted based on our historical volatility. (c) The risk-free interest rate is based on the U.S. Treasury yield for a period commensurate with the expected life of the option. We estimate forfeitures at the time of grant and periodically revise those estimates in subsequent periods if actual forfeitures differ from those estimates. Stock-based compensation expense is recorded only for those awards expected to vest using estimated forfeiture rates based on historical forfeiture data. As of December 31, 2020, there remained approximately $0.6 million of unearned compensation expense related to unvested stock options to be recognized over a weighted average term of 0.8 years. The weighted average grant date fair value was $1.82 Restricted Stock Units The following table summarizes restricted stock activity for grants to certain employees and independent members of the board of directors in our restricted stock units: Restricted Stock Units Weighted Average Numbers of Grant Date Units Fair Value Balance at December 31, 2019 3,846,608 $ 8.03 Granted 3,716,974 3.94 Vested (1,149,957 ) 8.50 Forfeited (723,816 ) 7.41 Balance at December 31, 2020 5,689,809 $ 5.34 During 2020 and 2019, we granted market-based restricted stock units to certain members of our senior management team. The number of shares ultimately issued to the recipient is based on the total shareholder return (“TSR”) of our common stock as compared to the TSR of the common stock of a peer group comprised of each member of the Russell 2000 Small Cap Market Index over a three-year three-year three-year As of December 31, 2020, there remained approximately $11.9 million of unearned compensation expense related to unvested restricted stock units to be recognized over a weighted average term of 1.5 years. The restricted stock units include a combination of time-based and performance-based vesting. Employee Stock Purchase Plan Our Board of Directors adopted an Employee Stock Purchase Plan (“ESPP”) in February 2015, which became effective on May 19, 2015 following stockholder approval. The ESPP provides for up to an aggregate of 1.3 million shares of our common stock may be made available for sale under the plan to eligible employees. At the beginning of each six-month offering period under the ESPP each participant is deemed to have been granted an option to purchase shares of our common stock equal to the amount of their payroll deductions during the period, but in any event not more than five percent of the employee’s eligible compensation, subject to certain limitations. Such options may be exercised only to the extent of accumulated payroll deductions at the end of the offering period, at a purchase price per share equal to 85% of the fair market value of our common stock at the beginning or end of each offering period, whichever is less. On December 10, 2020, the Compensation Committee of the Board of Directors determined we would not start a new offering period for the ESPP until we have an opportunity to seek shareholder approval of an amended and restated ESPP. As of December 31, 2020, there were a de minimis number of shares available for future issuance under the ESPP. Information related to shares issued or to be issued in connection with the ESPP based on employee contributions and the range of purchase prices is as follows: December 31, December 31, 2020 2019 Shares issued or to be issued 516,563 212,476 Range of purchase prices $1.54 - $1.56 $4.73 - $4.90 We record stock-based compensation expense related to the discount provided to participants. Also, we use the Black-Scholes option-pricing model to calculate the grant-date fair value of shares issued under the employee stock purchase plan. We recognize expense related to shares purchased through the employee stock purchase plan ratably over the offering period. We recognized $0.4 million

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	1 4 . The accounting standard for fair value measurements, among other things, defines fair value, establishes a consistent framework for measuring fair value and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. The accounting standard establishes a three-tier fair value hierarchy which prioritizes the inputs used in measuring fair value as follows: Level 1 Observable input such as quoted prices in active markets for identical assets or liabilities; Level 2 Observable inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and Level 3 Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. Assets and liabilities measured at fair value are based on one or more of three valuation techniques identified in the tables below. Where more than one technique is noted, individual assets or liabilities were valued using one or more of the noted techniques. The valuation techniques are as follows: (a) Market approach: Prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities; (b) Cost approach: Amount that would be currently required to replace the service capacity of an asset (current replacement cost); and (c) Income approach: Valuation techniques to convert future amounts to a single present amount based on market expectations (including present value techniques). On a recurring basis, we measure certain financial assets and liabilities at fair value, including our money market funds, foreign exchange forward contracts, and interest rate derivatives contracts. The accounting standard for fair value measurements defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. In determining fair value, we utilize valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as consider counterparty and its credit risk in its assessment of fair value. Financial Assets and Liabilities The following tables present our financial assets and liabilities measured at fair value on a recurring basis at December 31, 2020 and 2019: Quoted Prices Significant in Active Other Markets for Observable Identical Assets Inputs Valuation 2020 (Level 1) (Level 2) Technique Financial assets Money market funds $ 262,135 $ 262,135 $ — (a) Foreign exchange derivatives 466 — 466 (a) $ 262,601 $ 262,135 $ 466 Quoted Prices Significant in Active Other Markets for Observable Identical Assets Inputs Valuation 2019 (Level 1) (Level 2) Technique Financial assets Money market funds $ 276,654 $ 276,654 $ — (a) $ 276,654 $ 276,654 $ — Financial liabilities Interest rate derivatives $ 986 $ — $ 986 (a) Foreign exchange derivatives 127 — 127 (a) $ 1,113 $ — $ 1,113 Our money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices in active markets for identical instruments. In addition to $262.1 million and $276.7 million invested in money market funds as of December 31, 2020 and 2019, respectively, we had $19.1 million and $19.7 million of cash invested in bank accounts as of December 31, 2020 and 2019, respectively. Our foreign exchange derivatives consist of forward contracts and are classified within Level 2 of the fair value hierarchy because they are valued based on observable inputs and are available for substantially the full term of our derivative instruments. We use foreign exchange forward contracts to fix the functional currency value of forecasted commitments, payments and receipts. The aggregate notional amount of the outstanding foreign exchange forward contracts was $14.9 million and $15.2 million at December 31, 2020 and 2019, respectively. Our foreign exchange forward contracts contain netting provisions to mitigate credit risk in the event of counterparty default, including payment default and cross default. At December 31, 2020 and 2019, the fair value of our counterparty default exposure was less than $1.0 million and spread across several highly rated counterparties. Our interest rate derivatives are classified within Level 2 of the fair value hierarchy because they are valued based on observable inputs and are available for substantially the full term of our derivative instruments. Our interest rate risk relates primarily to U.S. dollar borrowings, partially offset by U.S. dollar cash investments. We have historically used interest rate derivative instruments to manage our earnings and cash flow exposure to changes in interest rates by converting floating-rate debt into fixed-rate debt. There were no aggregate notional amounts outstanding of the interest rate derivative instruments We believe we do not have significant concentrations of credit risk arising from our interest rate derivative instruments, whether from an individual counterparty or a related group of counterparties. We manage the concentration of counterparty credit risk on our interest rate derivatives instruments by limiting acceptable counterparties to a diversified group of major financial institutions with investment grade credit ratings, limiting the amount of credit exposure to each counterparty, and actively monitoring their credit ratings and outstanding fair values on an ongoing basis. Furthermore, none of our derivative transactions contain provisions that are dependent on our credit ratings from any credit rating agency. We also employ master netting arrangements that reduce our counterparty payment settlement risk on any given maturity date to the net amount of any receipts or payments due between us and the counterparty financial institution. Thus, the maximum loss due to counterparty credit risk is limited to the unrealized gains in such contracts net of any unrealized losses should any of these counterparties fail to perform as contracted. Although these protections do not eliminate concentrations of credit risk, as a result of the above considerations, we do not consider the risk of counterparty default to be significant. Non-Financial Assets and Liabilities Our non-financial assets, which include goodwill, other intangible assets, property, plant, and equipment, and pre-publication costs, are not required to be measured at fair value on a recurring basis. However, if certain trigger events occur, or if an annual impairment test is required, we evaluate the non-financial assets for impairment. If an impairment did occur, the asset is required to be recorded at the estimated fair value. An impairment analysis was performed for the preparation of the first quarter report, as there were triggering events for the three months ended March 31, 2020 related to the decline in our stock price attributed to the market environment, which resulted in a goodwill impairment The following table presents our nonfinancial assets measured at fair value on a nonrecurring basis during 2020: Significant Unobservable Inputs Total Valuation December 31, 2020 (Level 3) Impairment Technique Nonfinancial assets Goodwill $ 437,977 $ 437,977 $ 279,000 (c) $ 437,977 $ 437,977 $ 279,000 In evaluating goodwill for impairment, we first compare our reporting unit’s fair value to its carrying value. We estimate the fair values of our reporting units by considering our market capitalization and other judgements. Impairment recorded for goodwill for the year ended December 31, 2020 was $279.0 million. There was no impairment recorded for goodwill for the years ended December 31, 2019 and 2018. We perform an impairment test for our other intangible assets by comparing the assets fair value to its carrying value. Fair value is estimated based on recent market transactions, where available, and projected discounted cash flows, if reasonably estimable. There was no impairment of other intangible assets for the years ended December 31, 2020, 2019 and 2018. Non-Marketable Investments At December 31, 2020 and 2019, the carrying value of our non-marketable investments, which were comprised of equity interests in educational technology private partnerships, was $4.4 million and $2.3 million, respectively. The amounts are included in other assets in our consolidated balance sheets. Our non-marketable investments are accounted for using the cost method and are adjusted for observable transactions as appropriate. Gains from non-marketable investments were $2.1 million for the year ended December 31, 2020 and are included in gain on investments in our consolidated statements of operations. Fair Value of Debt The following table presents the carrying amounts and estimated fair market values of our debt at December 31, 2020 and 2019. The fair value of debt is deemed to be the amount at which the instrument could be exchanged in an orderly transaction between market participants at the measurement date. December 31, 2020 December 31, 2019 Carrying Estimated Carrying Estimated Amount Fair Value Amount Fair Value $380,000 Term loan $ 346,091 $ 331,382 $ 361,294 $ 360,391 $306,000 Senior secured notes 297,601 $ 304,297 295,893 301,441 The fair market values of our debt were estimated based on quoted market prices on a private exchange for those instruments that are traded and are classified as Level 2 within the fair value hierarchy at December 31, 2020 and 2019. The fair market values require varying degrees of management judgment. The factors used to estimate these values may not be valid on any subsequent date. Accordingly, the fair market values of the debt presented may not be indicative of their future values.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	1 5 . We are involved in ordinary and routine litigation and matters incidental to our business, including claims alleging breach of contract and seeking royalty payments. Litigation alleging infringement of copyrights and other intellectual property rights is also common in the educational publishing industry. There have been various settled, pending and threatened litigation that allege we exceeded the print run limitation or other restrictions in licenses granted to us to reproduce photographs in our textbooks. While we may incur a loss associated with certain pending or threatened litigation, we are not able to estimate such amount, if any, but we do not expect any of these matters to have a material adverse effect on our results of operations, financial position or cash flows. We have insurance over such amounts and with coverage and deductibles as management believes is reasonable. There can be no assurance that our liability insurance will cover all events or that the limits of coverage will be sufficient to fully cover all liabilities. In April 2019, we were notified of an unasserted claim by the Commonwealth of Puerto Rico with regards to payments in the amount of approximately $33.0 million that we received in the normal course of business during the four year period prior to the May 3, 2017 bankruptcy petition of the Commonwealth public instrumentalities. Management believes, based on discussions with its legal counsel, that we have meritorious defenses against such unasserted claim. The Company will vigorously defend this matter if such claim is asserted. In September 2019, we were notified of an unasserted claim by Riverside Assessments LLC (“Riverside”) with regard to purported breaches of the Asset Purchase Agreement between the Company and Riverside dated September 12, 2018 (“APA”) and the Transition Services Agreement between the Company and Riverside dated October 1, 2018. Management believes, based on discussions with its legal counsel, that we have meritorious defenses against such unasserted claim. With regard to the alleged breaches of the APA, the APA provides that the Company may be liable only for that portion of Riverside’s damages that exceeds $1.4 million, and in an amount that shall not exceed $1.4 million, which we believe would be the maximum exposure. For damages above $2.8 million, Riverside obtained a representation and warranty insurance policy as required by the APA. The Company will vigorously defend this matter if such claim is asserted. In January 2018, Vanderbilt University (“Vanderbilt”) filed a complaint against the Company and others in connection with a license agreement originally entered into between Vanderbilt and Scholastic Inc. in 1997 and subsequently assigned to the Company as part of our acquisition of Scholastic’s Educational Technology and Services business pursuant to the stock and asset purchase agreement dated April 23, 2015. Vanderbilt alleges entitlement to additional royalties in connection with READ 180 and other products acquired from Scholastic and alleges trademark infringement in the marketing of these products. The Company is vigorously defending this matter. The case is scheduled for trial in August 2021. In connection with an agreement with a development content provider, we agreed to act as guarantor to that party’s loan to finance such development. Such guarantee is expected to remain until 2022. Under the guarantee, we believe the maximum future payments to approximate $10.1 million. In the unlikely event that we are required to make payments on behalf of the development content provider, we would have recourse against the development content provider. We were contingently liable for $1.4 million and $2.5 million of performance-related surety bonds for our operating activities as of December 31, 2020 and 2019, respectively. An aggregate of $18.8 million We routinely enter into standard indemnification provisions as part of license agreements involving use of our intellectual property. These provisions typically require us to indemnify and hold harmless licensees in connection with any infringement claim by a third-party relating to the intellectual property covered by the license agreement. Although the term of these provisions and the maximum potential amounts of future payments we could be required to make is not limited, we have never incurred any costs to defend or settle claims related to these types of indemnification provisions. We therefore believe the estimated fair value of these provisions is inconsequential and have no liabilities recorded for them as of December 31, 2020 and 2019.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity	1 6 . Accumulated Other Comprehensive Loss Accumulated other comprehensive loss consisted of the following at December 31, 2020, 2019 and 2018: 2020 2019 2018 Net change in pension and benefit plan liabilities $ (48,966 ) $ (39,757 ) $ (41,557 ) Foreign currency translation adjustments (6,650 ) (6,420 ) (5,909 ) Unrealized loss on short-term investments (90 ) (90 ) (99 ) Net change in unrealized loss on derivative instruments (18 ) (1,005 ) 2,381 $ (55,724 ) $ (47,272 ) $ (45,184 ) Amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2020, 2019 and 2018 relating to the amortization of defined benefit pension and postretirement benefit plans totaled approximately $(2.4) million, $(0.9) million and $(0.9) million, respectively, and affected the selling and administrative line item in the consolidated statement of operations. These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	1 7 . There were no related party transactions during 2020 and In November 2019, Anchorage Capital Group, L.L.C. (“Anchorage”), a significant stockholder in the Company at the time and a former partner of which was serving on the Company’s board of directors, participated as a lender in the refinancing of the Company’s debt, acquiring $20.0 million out of the $306.0 million in aggregate principal amount of 9.000% Senior Secured Notes due 2025 (the “Notes”) issued by the Company and becoming a lender under the Company’s second amended and restated term loan credit agreement (the “Term Loan Credit Agreement”) with a commitment of $15.0 million out of the $380.0 million in initial principal amount of the term loan. As of December 10 , 2020, Anchorage no longer had an ownership interest in the Company. Anchorage’s participation in the refinancing was on the same terms as all the other lenders. Refer to note 8 for additional information about the Notes and the Term Loan Credit Agreement.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	1 8 . The following table sets forth the computation of basic and diluted earnings per share (“EPS”): For the Year For the Year For the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Numerator Loss from continuing operations $ (479,838 ) $ (213,833 ) $ (137,457 ) Earnings from discontinued operations, net of tax — — 12,833 Gain on sale of discontinued operations, net of tax — — 30,469 Income from discontinued operations, net of tax — — 43,302 Net loss attributable to common stockholders $ (479,838 ) $ (213,833 ) $ (94,155 ) Denominator Weighted average shares outstanding Basic and diluted 125,455,487 124,152,984 123,444,943 Net loss per share attributable to common Stockholders Basic and diluted: Continuing operations $ (3.82 ) $ (1.72 ) $ (1.11 ) Discontinued operations — — 0.35 Net loss $ (3.82 ) $ (1.72 ) $ (0.76 ) As we incurred a net loss in each of the periods presented above, all outstanding stock options and restricted stock units for those periods have an anti-dilutive effect and therefore are excluded from the computation of diluted weighted average shares outstanding. Accordingly, basic and diluted weighted average shares outstanding are equal for such periods. The following table summarizes our weighted average outstanding common stock equivalents that were anti-dilutive attributable to common stockholders during the periods, and therefore excluded from the computation of diluted EPS: For the Year For the Year For the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Stock options 1,897,212 2,765,826 3,406,171 Restricted stock units 4,133,531 3,342,923 2,793,680

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Segment Reporting	1 9 . As of December 31, 2020, we had two reportable segments (Education and HMH Books & Media). Our Education segment provides educational products, technology platforms and services to meet the diverse needs of today’s classrooms. These products and services include print and digital content in the form of textbooks, digital courseware, instructional aids, educational assessment and intervention solutions, which are aimed at improving achievement and supporting learning for students who are not keeping pace with peers, professional development and school reform services. Our HMH Books & Media segment primarily develops, markets and sells consumer books in print and digital formats and licenses book rights to other publishers and electronic businesses in the United States and abroad. The principal distribution channels for HMH Books & Media products are retail stores, both physical and online, and wholesalers. We measure and evaluate our reportable segments based on net sales and segment Adjusted EBITDA from continuing operations. We exclude from our segments certain corporate-related expenses, as our corporate functions do not meet the definition of a segment, as defined in the accounting guidance relating to segment reporting. In addition, certain transactions or adjustments that our Chief Operating Decision Maker considers to be non-operational, such as amounts related to goodwill and other intangible asset impairment charges, derivative instruments charges, acquisition/disposition-related activity, restructuring, severance costs, equity compensation charges, gains or losses from investments, Year Ended December 31, HMH Corporate/ (in thousands) Education Books & Media Other 2020 Net sales $ 839,553 $ 191,739 $ — Segment Adjusted EBITDA 145,862 26,627 (40,649 ) 2019 Net sales $ 1,210,646 $ 180,028 $ — Segment Adjusted EBITDA 196,907 14,908 (46,077 ) 2018 Net sales $ 1,122,689 $ 199,728 $ — Segment Adjusted EBITDA 210,604 21,942 (40,418 ) The following table disaggregates our net sales by major source: Year Ended December 31, 2020 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 459,350 $ — $ 459,350 Extensions businesses (2) 380,203 — 380,203 Books & Media — 191,739 191,739 Net sales $ 839,553 $ 191,739 $ 1,031,292 Year Ended December 31, 2019 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 578,675 $ — $ 578,675 Extensions businesses (2) 631,971 — 631,971 Books & Media — 180,028 180,028 Net sales $ 1,210,646 $ 180,028 $ 1,390,674 Year Ended December 31, 2018 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 538,166 $ — $ 538,166 Extensions businesses (2) 584,523 — 584,523 Books & Media — 199,728 199,728 Net sales $ 1,122,689 $ 199,728 $ 1,322,417 (1) Comprehensive solutions primarily for reading, literature, math, science and social studies programs. (2) Primarily consists of our Heinemann brand, intervention, supplemental and professional services. Reconciliation of Segment Adjusted EBITDA to the consolidated statements of operations is as follows: Years Ended December 31, (in thousands) 2020 2019 2018 Education Adjusted EBITDA $ 145,862 $ 196,907 $ 210,604 HMH Books & Media Adjusted EBITDA 26,627 14,908 21,942 Total Segment Adjusted EBITDA 172,489 211,815 232,546 Corporate/Other Adjusted EBITDA (40,649 ) (46,077 ) (40,418 ) Interest expense (65,959 ) (48,778 ) (45,680 ) Interest income 899 3,157 2,550 Depreciation expense (50,715 ) (61,475 ) (75,116 ) Amortization expense—film asset (13,953 ) (9,835 ) (6,057 ) Amortization expense (171,821 ) (201,382 ) (170,903 ) Non-cash charges—stock compensation (11,573 ) (13,968 ) (13,248 ) Non-cash charges—loss on derivative instruments 672 (899 ) (1,374 ) Non-cash charges—asset impairment charges (279,000 ) — — Inventory obsolescence related to strategic transformation plan — (9,758 ) — Fees, expenses or charges for equity offerings, debt or acquisitions/dispositions (1,080 ) (6,327 ) (2,883 ) Restructuring/severance and other charges (33,643 ) (21,742 ) (11,478 ) Gain on investments 2,091 — — Gain on sale of assets — — 201 Loss on extinguishment of debt — (4,363 ) — Loss before taxes (492,242 ) (209,632 ) (131,860 ) (Provision) benefit for income taxes 12,404 (4,201 ) (5,597 ) Net loss from continuing operations $ (479,838 ) $ (213,833 ) $ (137,457 ) Segment information as of December 31, 2020 and 2019 is as follows: (in thousands) 2020 2019 Total assets—Education segment $ 1,520,504 $ 1,971,553 Total assets—HMH Books & Media segment 175,710 186,318 Total assets—Corporate and Other 324,912 355,301 Total consolidated assets $ 2,021,126 $ 2,513,172 The following represents long-lived assets (property, plant, and equipment) outside of the United States, which are substantially in Ireland. All other long-lived assets are located in the United States. (in thousands) 2020 2019 Long-lived assets—International $ 228 $ 113 The following is a schedule of net sales by geographic region: (in thousands) Year Ended December 31, 2020 Net sales—U.S. $ 997,178 Net sales—International 34,114 Total net sales $ 1,031,292 Year Ended December 31, 2019 Net sales—U.S. $ 1,327,833 Net sales—International 62,841 Total net sales $ 1,390,674 Year Ended December 31, 2018 Net sales—U.S. $ 1,249,568 Net sales—International 72,849 Total net sales $ 1,322,417

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2020
Valuation And Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	20 . Balance at Balance at Beginning Utilization of End of Year Net Charges Allowances of Year 2020 Allowance for doubtful accounts $ 3,015 $ 1,589 $ (615 ) $ 3,989 Reserve for returns 16,679 33,847 (35,952 ) 14,574 Reserve for royalty advances 119,695 16,552 (39,592 ) 96,655 Deferred tax valuation allowance 583,505 81,475 (2,412 ) 662,568 2019 Allowance for doubtful accounts $ 2,173 $ 1,909 $ (1,067 ) $ 3,015 Reserve for returns 18,559 41,654 (43,534 ) 16,679 Reserve for royalty advances 117,797 16,500 (14,602 ) 119,695 Deferred tax valuation allowance 562,392 23,707 (2,594 ) 583,505 2018 Allowance for doubtful accounts $ 2,508 $ 128 $ (463 ) $ 2,173 Reserve for returns 20,580 36,395 (38,416 ) 18,559 Reserve for royalty advances 103,606 17,301 (3,110 ) 117,797 Deferred tax valuation allowance 571,653 (7,667 ) (1,594 ) 562,392

Quarterly Results of Operations

Quarterly Results of Operations (Unaudited)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations (Unaudited)	2 1 . Three Months Ended March 31, June 30, September 30, December 31, 2020: Net sales $ 189,925 $ 251,216 $ 386,590 $ 203,561 Gross profit 63,450 90,389 167,415 65,986 Operating (loss) income (338,176 ) (22,212 ) 272 (68,973 ) Net loss (345,973 ) (38,168 ) (12,552 ) (83,145 ) Net loss per share attributable to common stockholders Basic: Net loss $ (2.77 ) $ (0.30 ) $ (0.10 ) $ (0.66 ) Diluted: Net loss $ (2.77 ) $ (0.30 ) $ (0.10 ) $ (0.66 ) 2019: Net sales $ 194,635 $ 388,896 $ 565,668 $ 241,475 Gross profit 57,893 156,055 273,481 59,065 Operating (loss) income (101,835 ) (30,253 ) 77,871 (108,947 ) Net (loss) income (117,362 ) (40,613 ) 69,260 (125,118 ) Net (loss) income per share attributable to common stockholders Basic: Net (loss) income $ (0.95 ) $ (0.33 ) $ 0.56 $ (1.01 ) Diluted: Net (loss) income $ (0.95 ) $ (0.33 ) $ 0.55 $ (1.01 ) Our net sales, operating profit or loss and net cash provided by or used in operations are impacted by the inherent seasonality of the academic calendar. Consequently, the performance of our businesses may not be comparable quarter to consecutive quarter and should be considered on the basis of results for the whole year or by comparing results in a quarter with results in the same quarter for the previous year. During the fourth quarter of 2020, we recorded an adjustment of $17.0 million and $1.0 million to increase both the goodwill impairment charge and income tax benefit recorded, respectively, to correct an error of the previously recorded goodwill impairment of $262.0 million and related income tax benefit in the first quarter of 2020. Management believes these adjustments are not material to the current period financial statements or any prior periods.

Significant Accounting Polici_2

Significant Accounting Policies and Recent Accounting Standards (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires the use of estimates, assumptions and judgments by management that affect the reported amounts of assets, liabilities, revenues, expenses, and related disclosure of contingent assets and liabilities in the amounts reported in the financial statements and accompanying notes. On an ongoing basis, we evaluate our estimates and assumptions including, but not limited to, book returns, deferred revenue and related standalone selling price estimates, allowance for bad debts, recoverability of advances to authors, valuation of inventory, financial instruments valuation, income taxes, pensions and other postretirement benefits obligations, contingencies, litigation, depreciation and amortization periods, and the recoverability of long-term assets such as property, plant, and equipment, capitalized pre-publication costs, other identified intangibles and goodwill. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets, liabilities and equity and the amount of revenues and expenses. The full extent to which the COVID-19 pandemic will directly or indirectly impact our business, results of operations and financial condition will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat it, as well as the economic impact on local, regional, national and international customers and markets. Actual results may differ from those estimates.
Revenue Recognition	Revenue Recognition Revenue is recognized when a customer obtains control of promised goods or services, in an amount that reflects the consideration which we expect to receive in exchange for those goods or services. To determine revenue recognition for arrangements that we determine are within the scope of the new revenue recognition accounting standard, we perform the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. At contract inception, we assess the goods or services promised within each contract and determine those that are performance obligations and assess whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Revenue is measured as the amount of consideration we expect to receive in exchange for transferring products or services to a customer. To the extent the transaction price includes variable consideration, which generally reflects estimated future product returns, we estimate the amount of variable consideration that should be included in the transaction price utilizing the expected value method to which we expect to be entitled. Variable consideration is included in the transaction price if, in our judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Estimates of variable consideration and the determination of whether to include estimated amounts in the transaction price are based largely on all information (historical, current and forecasted) that is reasonably available. Sales, value add, and other taxes collected on behalf of third parties are excluded from revenue. We estimate the collectability of contracts upon execution. For contracts with rights of return, the transaction price is adjusted to reflect the estimated returns for the arrangement on these sales and is made at the time of sale based on historical experience by product line or customer. The transaction prices allocated are adjusted to reflect expected returns and are based on historical return rates and sales patterns. Shipping and handling fees charged to customers are included in net sales. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. We do not assess whether a significant financing component exists if the period between when we perform our obligations under the contract and when the customer pays is one year or less. Significant financing components’ income is included in interest income. Contracts are sometimes modified to account for changes in contract specifications and requirements. Contract modifications exist when the modification either creates new, or changes the existing, enforceable rights and obligations. Generally, contract modifications are for products or services that are not distinct from the existing contract due to the inability to use, consume or sell the products or services on their own to generate economic benefits and are accounted for as if they were part of that existing contract. The effect of such a contract modification on the transaction price and measure of progress for the performance obligation to which it relates is recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. Physical product revenue is recognized when the customer obtains control of our product, which occurs at a point in time, and may be upon shipment or upon delivery based on the contractual shipping terms of a contract. Revenues from static digital content commence upon delivery to the customer of the digital entitlement that is required to access and download the content and is typically recognized at a point in time. Revenues from subscription software licenses, related hosting services and product support are recognized evenly over the license term as we believe this best represents the pattern of transfer to the customer. The perpetual software licenses provide the customer with a functional license to our products and their related revenues are recognized when the customer receives entitlement to the software. For the technical services provided to customers in connection with the software license, including hosting services related to perpetual licenses, we recognize revenue upon delivery of the services. As the invoices are based on each day of service, this is directly linked to the transfer of benefit to the customer. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. We enter into certain contracts that have multiple performance obligations, one or more of which may be delivered subsequent to the delivery of other performance obligations. These performance obligations may include print and digital media, professional development services, training, software licenses, access to hosted content, and various services related to the software including, but not limited to hosting, maintenance and support, and implementation. We allocate the transaction price based on the estimated relative standalone selling prices of the promised products or services underlying each performance obligation. We determine standalone selling prices based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, we estimate the standalone selling price taking into account available information such as market conditions and internally approved standard pricing discounts related to the performance obligations. Generally, our performance obligations include print and digital textbooks and instructional materials, trade books, reference materials, formative assessment materials and multimedia instructional programs; licenses to book rights and content; access to hosted content; and services including professional development, consulting and training. Our contracts may also contain software performance obligations including perpetual and subscription-based licenses and software maintenance and support services.
Accounts Receivable	Accounts Receivable Accounts receivable include amounts billed and currently due from customers and are recorded net of allowances for doubtful accounts and reserves for returns. In the normal course of business, we extend credit to customers that satisfy predefined criteria. We estimate the collectability of our receivables and develop those estimates to reflect the risk of credit loss. Allowances for doubtful accounts are established through the evaluation of accounts receivable aging, prior collection experience, current conditions and reasonable and supportable forecasts of the economic conditions that will exist through the contractual life of the financial asset. We monitor our ongoing credit exposure through an active review of collection trends and specific facts and circumstances. Our activities include monitoring the timeliness of payment collection and performing timely account reconciliations.
Contract Assets	Contract Assets Contract assets include unbilled amounts where revenue is recognized over time as the services are delivered to the customer based on the extent of progress towards completion and revenue recognized exceeds the amount billed to the customer, and right of payment is not subject to the passage of time. Amounts may not exceed their net realizable value. Contract assets are included in prepaid expenses and other assets on our consolidated balance sheets.
Deferred Commissions	Deferred Commissions Our incremental direct costs of obtaining a contract, which consist of sales commissions, are deferred and amortized over the period of contract performance. Applying the practical expedient, we recognize sales commission expense when incurred if the amortization period of the assets that we otherwise would have recognized is one year or less. Amortization expense is included in selling and administrative expenses.
Deferred Revenue	Deferred Revenue Our contract liabilities consist of advance payments and billings in excess of revenue recognized and are classified as deferred revenue on our consolidated balance sheets. Our contract assets and liabilities are accounted for and presented on a net basis as either a contract asset or contract liability at the end of each reporting period. We classify deferred revenue as current or noncurrent based on the timing of when we expect to recognize revenue. In order to determine revenue recognized in the period from contract liabilities, we first allocate revenue to the individual contract liability balance outstanding at the beginning of the period until the revenue exceeds that balance. If additional advances are received on those contracts in subsequent periods, we assume all revenue recognized in the reporting period first applies to the beginning contract liability as opposed to a portion applying to the new advances for the period.
Advertising Costs and Sample Expenses	Advertising Costs and Sample Expenses Advertising costs are charged to selling and administrative expenses as incurred. Advertising costs were $12.1
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist primarily of cash in banks and highly liquid investment securities that have maturities of three months or less when purchased. The carrying amount of cash equivalents approximates fair value because of the short-term maturity of these investments.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded net of allowances for doubtful accounts and reserves for returns. In the normal course of business, we extend credit to customers that satisfy predefined criteria. We estimate the collectability of our receivables. Allowances for doubtful accounts are established through the evaluation of accounts receivable aging and prior collection experience to estimate the ultimate collectability of these receivables. Reserves for returns are based on historical return rates and sales patterns.
Inventories	Inventories Inventories are stated at the lower of weighted-average cost or net realizable value. The level of obsolete and excess inventory is estimated on a program or title level-basis by comparing the number of units in stock with past usage and the expected future demand. The expected future demand of a program or title is determined by the copyright year, the previous year’s usage, the subsequent years’ sales forecast, and known forward-looking trends including our development cycle to replace the title or program and competing titles or programs.
Property, Plant, and Equipment	Property, Plant, and Equipment Property, plant, and equipment are stated at cost, or in the case of assets acquired in business combinations, at fair value as of the acquisition date, less accumulated depreciation. Equipment under capital lease is stated at fair value at inception of the lease, less accumulated depreciation. Maintenance and repair costs are charged to expense as incurred, and renewals and improvements that extend the useful life of the assets are capitalized. Costs associated with developing film and episodic series assets are deferred if such amounts are expected to be recovered through future revenues. Film and episodic series costs are amortized on a pro rata basis of revenue earned and total revenue expected to be earned from the film or episodic series. Depreciation on property, plant, and equipment is calculated using the straight-line method over the estimated useful lives of the assets or, in the case of assets acquired in business combinations, over their remaining lives. Equipment held under capital leases and leasehold improvements are amortized using the straight-line method over the shorter of the lease term or estimated useful life of the asset. Estimated useful lives of property, plant, and equipment are as follows: Estimated Useful Life Building and building equipment 10 to 35 years Machinery and equipment 2 to 15 years Capitalized software and internal-use software 3 to 5 years Leasehold improvements Lesser of useful life or lease term Film and media Revenue earned
Capitalized Internal-Use Software and Software Development Costs	Capitalized Internal-Use Software and Software Development Costs Capitalized internal-use software and software is included in property, plant and equipment on the consolidated balance sheets. We capitalize certain costs related to obtaining or developing computer software for internal use including external customer-facing websites. Costs incurred during the application development stage, including external direct costs of materials and services, and payroll and payroll related costs for employees who are directly associated with the internal-use software project, are capitalized and amortized on a straight-line basis over the expected useful life of the related software. The application development stage includes design of chosen path, software configuration and integration, coding, hardware installation and testing. Costs incurred during the preliminary project stage, as well as maintenance, training and upgrades that do not result in additional functionality subsequent to general release are expensed as incurred. Certain computer software development costs for software that is to be sold or marketed are capitalized in the consolidated balance sheets. Capitalization of computer software development costs begins upon the establishment of technological feasibility. We define the establishment of technological feasibility as a working model. Amortization of capitalized computer software development costs is provided on a product-by-product basis using the straight-line method, beginning upon commercial release of the product and continuing over the remaining estimated economic life of the product. The carrying amounts of computer software development costs are annually compared to net realizable value and impairment charges are recorded, as appropriate, when amounts expected to be realized are lower. We review internal-use software and software development costs for impairment. For the years ended December 31, 2020, 2019 and 2018, there was no impairment of internal-use software and software developments costs.
Pre-publication Costs	Pre-publication Costs We capitalize the art, prepress, manuscript and other costs incurred in the creation of the master copy of a book or other media (the “pre-publication costs”). Pre-publication costs are primarily amortized from the year of sale over five years using the sum-of-the-years-digits method, which is an accelerated method for calculating an asset’s amortization. Under this method, the amortization expense recorded for a pre-publication cost asset is approximately 33% (year 1), 27% (year 2), 20% (year 3), 13% (year 4) and 7% (year 5). This policy is used throughout the Company, except for the HMH Books & Media young readers and general interest books, which generally expenses such costs as incurred. Additionally, pre-publication costs recorded in connection with the acquisition of the EdTech business are amortized over 7 years on a projected sales pattern. The amortization methods and periods chosen best reflects the pattern of expected sales generated from individual titles or programs. We periodically evaluate the remaining lives and recoverability of capitalized pre-publication costs, which are often dependent upon program acceptance by state adoption authorities. Amortization expense related to pre-publication costs for the years ended December 31, 2020, 2019 and 2018 were $126.2 million, $149.5 million and $109.3 million, respectively. We review pre-publication costs for impairment.
Goodwill and Indefinite-lived Intangible Assets	Goodwill and Indefinite-lived Intangible Assets Goodwill is the excess of the purchase price paid over the fair value of the net assets of the business acquired. Other intangible assets principally consist of branded trademarks and trade names, acquired publishing rights and customer relationships. Goodwill and indefinite-lived intangible assets (certain tradenames) are not amortized, but are reviewed at least annually for impairment or earlier, if an indication of impairment exists. Goodwill is allocated entirely to our Education reporting unit. Determining the fair value of a reporting unit is judgmental in nature and involves the use of significant estimates and assumptions. These estimates and assumptions include our market capitalization, selection of a control premium, and the determination of appropriate market comparables as well as the fair value of certain individual assets and liabilities. We have the option of first assessing qualitative factors to determine whether it is necessary to perform a quantitative impairment test for goodwill or we can perform the quantitative impairment test without performing the qualitative assessment. In performing the qualitative assessment, events and circumstances specific to the reporting unit and to the entity as a whole, such as macroeconomic conditions, industry and market considerations, overall financial performance and cost factors are considered when evaluating whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. If the fair value of a reporting unit exceeds the carrying value of the net assets assigned to a reporting unit, goodwill is considered not impaired and no further testing is required. If the carrying value of the net assets assigned to a reporting unit exceeds the fair value of a reporting unit, goodwill is deemed impaired and is written down to the extent of the difference between the fair value of the reporting unit and the carrying value We estimate the total fair value of the Education reporting unit by using one or more of various valuation techniques including an evaluation of our market capitalization and peer company multiples depending on the best approximation of fair value of the Education reporting unit in the current social and economic environment. With regard to indefinite-lived intangible assets, which includes the Houghton Mifflin Harcourt tradename at December 31, 2020 and 2019, the recoverability is evaluated using a one-step process whereby we determine the fair value by asset and then compare it to its carrying value to determine if the asset is impaired. We estimate the fair value by preparing a relief-from-royalty discounted cash flow analysis using forward looking revenue projections. The significant assumptions used in discounted cash flow analysis include: future net sales, a long-term growth rate, a royalty rate and a discount rate used to present value future cash flows and the terminal value of the Education reporting unit. The discount rate is based on the weighted-average cost of capital method at the date of the evaluation. Adverse changes in our market capitalization or peer company multiples by an equivalent amount could give rise to an impairment. We completed our annual goodwill impairment test as of October 1, 2020 using consistent methodologies and assumptions with those described during our event-driven tests We completed our annual indefinite-lived asset impairment tests as of October 1, 2020 and 2019. No indefinite-lived intangible assets were deemed to be impaired for the years ended December 31, 2020, 2019 and 2018.
Publishing Rights	Publishing Rights A publishing right is an acquired right that allows us to publish and republish existing and future works as well as create new works based on previously published materials. We determined the fair market value of the publishing rights arising from business combinations by discounting the after-tax cash flows projected to be derived from the publishing rights and titles to their net present value using a rate of return that accounts for the time value of money and the appropriate degree of risk. The useful life of the publishing rights is based on the lives of the various copyrights involved. We calculate amortization using the percentage of the projected operating income before taxes derived from the titles in the current year as a percentage of the total estimated operating income before taxes over the remaining useful life. Acquired publication rights, as well as customer-related intangibles with definitive lives, are primarily amortized on an accelerated basis over periods ranging from 3 to 20 years. We review our publishing rights for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. No publishing rights were deemed to be impaired for the years ended December 31, 2020, 2019 and 2018.
Impairment of Other Long-lived Assets	Impairment of Other Long-lived Assets We review our other long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. If the future undiscounted cash flows are less than their book value, impairment exists. The impairment is measured as the difference between the book value and the fair value of the underlying asset. Fair value is normally determined using an undiscounted cash flow model.
Severance	Severance We accrue postemployment benefits if the obligation is attributable to services already rendered, rights to those benefits accumulate, payment of benefits is probable, and amount of benefit is reasonably estimated. Postemployment benefits include severance benefits. Subsequent to recording such accrued severance liabilities, changes in market or other conditions may result in changes to assumptions upon which the original liabilities were recorded that could result in an adjustment to the liabilities.
Royalty Advances	Royalty Advances Royalty advances to authors are capitalized and represent amounts paid in advance of the sale of an author’s product and are recovered as earned. As advances are recorded, a partial reserve may be recorded immediately based primarily upon historical sales experience. Additionally, advances are evaluated periodically to determine if they are expected to be recovered on a title-by-title basis, with consideration given to the other titles in the author’s portfolio also earning against the outstanding advance. Any portion of a royalty advance that is not expected to be recovered is fully reserved. The reserve for royalty advances is reported as a reduction of the royalty advances to authors balance.
Leases	Leases On January 1, 2019, we adopted the new lease accounting standard using the modified retrospective method. We applied the guidance to each lease as of January 1, 2019 with a cumulative effect adjustment to the opening balance of accumulated deficit as of that date. The standard requires lessees to recognize a lease liability and a right of use asset on the balance sheet for operating leases. Right of use assets represent our right to use an underlying asset for the lease term, and lease liabilities represent our obligation to make lease payments arising from the lease. Right of use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. Accounting for finance leases is substantially unchanged. Prior comparative periods were not adjusted. We elected the package of practical expedients permitted under the transition guidance within the new standard, which allowed us to not reassess whether any expired or existing contracts are or contain leases, carry forward the historical lease classification and to not reassess initial direct costs for any existing leases. We did not elect the hindsight practical expedient to determine the lease term for existing leases. Upon implementation of the new guidance, we have elected the practical expedients to combine lease and non-lease components, and to not recognize right of use assets and lease liabilities for short-term leases. The adoption of this guidance impacted our consolidated balance sheets due to the recognition of the lease rights and obligations related to our office space, automobile fleet and office equipment leases as assets and liabilities of approximately $148.0 million and $161.0 million, respectively. The adjustment to accumulated deficit of approximately $0.8 million related to a previously recorded deferred gain on the sale leaseback of a warehouse. The impact on our results of operations and cash flows was not material. Under the new lease accounting standard, we determine if an arrangement is a lease at inception. Right of use assets and lease liabilities are recognized at commencement date based on the present value of remaining lease payments over the lease term. For this purpose, we consider only payments that are fixed and determinable at the time of commencement. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. Our incremental borrowing rate is a hypothetical rate based on our understanding of what our credit rating would be. The right of use asset also includes any lease payments made prior to commencement and is recorded net of any lease incentives received. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise such options. When determining the probability of exercising such options, we consider contract-based, asset-based, entity-based, and market-based factors. Our lease agreements may contain variable costs such as common area maintenance, insurance, real estate taxes or other costs. Variable lease costs are expensed as incurred on our consolidated statements of operations. Our lease agreements generally do not contain any residual value guarantees or restrictive covenants. Operating leases are included in operating lease assets and operating lease liabilities on our consolidated balance sheets. Finance leases are included in property, plant, and equipment, and other liabilities on our consolidated balance sheets.
Income Taxes	Income Taxes We record income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax basis, and operating loss and tax credit carryforwards. Our consolidated financial statements contain certain deferred tax assets which have arisen primarily as a result of interest expense limitations, as well as other temporary differences between financial and tax accounting. We establish a valuation allowance if the likelihood of realization of the deferred tax assets is reduced based on an evaluation of objectively verifiable evidence. Significant management judgment is required in determining our provision for income taxes, our deferred tax assets and liabilities and any valuation allowance recorded against those deferred tax assets. We evaluate the weight of all available evidence to determine whether it is more likely than not that some portion or all of the deferred income tax assets will not be realized. We also evaluate any uncertain tax positions and only recognize the tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50 percent likelihood of being realized upon settlement. We record a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. Any change in judgment related to the expected ultimate resolution of uncertain tax positions is recognized in earnings in the period in which such change occurs. Interest and penalties, if any, related to unrecognized tax benefits are recorded in income tax expense.
Stock-Based Compensation	Stock-Based Compensation Certain employees and directors have been granted stock options, restricted stock and restricted stock units in our common stock. Stock-based compensation expense reflects the fair value of stock-based awards measured at the grant date and recognized over the relevant service period. We estimate the fair value of each stock-based award on the measurement date using the current market price based on the target value of the award for restricted stock and restricted stock units, the Monte Carlo simulation for market-based restricted stock units and the Black-Scholes valuation model for stock options. We recognize stock-based compensation expense over the awards requisite service period on a straight-line basis for time-based stock options, restricted stock and restricted stock units and on a graded basis for restricted stock and restricted stock units that are contingent on the achievement of performance conditions.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as changes in the equity of an enterprise except those resulting from stockholder transactions. The amounts shown on the consolidated statements of stockholders’ equity and comprehensive loss relate to the cumulative effect of changes in pension and postretirement liabilities, foreign currency translation gain and loss adjustments, unrealized gains and losses on short-term investments and gains and losses on derivative instruments.
Foreign Currency Translation	Foreign Currency Translation The functional currency for each of our subsidiaries is the currency of the primary economic environment in which the subsidiary operates, generally defined as the currency in which the entity generates and expends cash. Foreign currency denominated assets and liabilities are translated into United States dollars at current rates as of the balance sheet date and the revenue, costs and expenses are translated at the average rates established during each reporting period. Cumulative translation gains or losses are recorded in equity as an element of accumulated other comprehensive income.
Financial Instruments	Financial Instruments Derivative financial instruments are employed to manage risks associated with interest rate exposures and are not used for trading or speculative purposes. We recognize all derivative instruments in our consolidated balance sheets at fair value. Changes in the fair value of derivatives are recognized periodically either in earnings or in stockholders’ equity as a component of accumulated other comprehensive loss, depending on whether the derivative financial instrument qualifies for hedge accounting and, if so, whether it qualifies as a fair value hedge or a cash flow hedge. Gains and losses on derivatives designated as hedges, to the extent they are effective, are recorded in other comprehensive loss, and subsequently reclassified to earnings to offset the impact of the hedged items when they occur. Changes in the fair value of derivatives not qualifying as hedges are reported in earnings. During 2020, 2019 and 2018, our interest rate swaps were designated as hedges and the majority qualified for hedge accounting. The interest rate derivative contracts matured on July 22, 2020. We recorded an
Treasury Stock	Treasury Stock We account for treasury stock under the cost method. When shares are reissued or retired from treasury stock they are accounted for at an average price. Upon retirement the excess over par value is charged against capital in excess of par value.
Net Loss per Share	Net Loss per Share Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average common shares outstanding during the period. Except where the result would be anti-dilutive, net loss per share is computed using the treasury stock method for the exercise of stock options. For periods in which the Company has reported net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders for the years ended December 31, 2020, 2019 and 2018.
Recent Accounting Standards	Recent Accounting Standards Recent accounting pronouncements, not included below, are not expected to have a material impact on our consolidated financial position or results of operations. Recently Issued Accounting Standards In December 2019, the Financial Accounting Standards Board (“FASB”) issued new guidance to simplify the accounting for income taxes by removing certain exceptions to the general principles, including simplification of areas such as franchise taxes, step-up in tax basis of goodwill, intraperiod allocations, separate entity financial statements and interim recognition of enactment of tax laws or rate changes. The standard will be effective in 2021, with early adoption permitted. We do not expect it to have a material impact on our consolidated financial statements. Recently Adopted Accounting Standards In August 2018, the FASB issued new guidance on a customer's accounting for implementation, set-up, and other upfront costs incurred in a cloud computing arrangement that is hosted by the vendor (i.e., a service contract). Under the new guidance, customers will apply the same criteria for capitalizing implementation costs as they would for an arrangement to develop or obtain internal use software. Accordingly, the guidance requires a customer to determine the stage of a project that the implementation activity relates to and the nature of the associated costs in order to determine whether those costs should be expensed as incurred or capitalized. The guidance also requires the customer to amortize the capitalized implementation costs as an expense over the term of the hosting arrangement. We adopted the guidance on January 1, 2020. The adoption of this guidance did not have a material impact on our consolidated financial statements. In January 2017, the FASB issued updated guidance to simplify the test for goodwill impairment by the elimination of Step 2 in the determination on whether goodwill should be considered impaired. The annual assessments are still required to be completed. We adopted the guidance on January 1, 2020. In June 2016, the FASB issued new guidance that requires credit losses on financial assets measured at amortized cost basis to be presented at the net amount expected to be collected, not based on incurred losses, as well as additional disclosures. The estimate of expected credit losses should consider historical information, current information, as well as reasonable and supportable forecasts, including estimates of prepayments. We adopted the guidance on January 1, 2020. The adoption of this guidance did not have a material impact on our consolidated financial statements. We are exposed to credit losses primarily through our accounts receivable. We develop estimates to reflect the risk of credit loss which are based on an evaluation of accounts receivable aging, prior collection experience, current conditions and reasonable and supportable forecasts of the economic conditions that will exist through the contractual life of the financial asset. We write off the asset when it is no longer deemed collectible. We monitor our ongoing credit exposure through an active review of collection trends. Our activities include monitoring the timeliness of payment collection and performing timely account reconciliations. At December 31, 2020, we reported allowances for doubtful accounts of $4.0 million, compared to $3.0 million at December 31, 2019, reflecting an increase of $1.6 million, prior to write-offs of $0.6 million for the year ended December 31, 2020. We are also exposed to losses on our royalty advances. Royalty advances to authors are capitalized and represent amounts paid in advance of the sale of an author’s product and are recovered immediately based primarily upon historical sales experience. Additionally, advances are evaluated periodically to determine if they are expected to be recovered on a title-by-title basis. Any portion of a royalty advance that is not expected to be recovered is fully reserved. At December 31, 2020, we reported a reserve for royalty advances of $96.7 million, compared to $119.7 million at December 31, 2019, reflecting a decrease of $23.0 million for the year ended December 31, 2020 In February 2016, the FASB issued guidance that primarily requires lessees to recognize most leases on their balance sheets but record expenses on their income statements in a manner similar to current accounting. We adopted the guidance on January 1, 2019 using the modified retrospective method and did not adjust comparative periods or modify disclosures in those comparative periods. In May 2014, the FASB issued new guidance related to revenue recognition. This new accounting standard replaced most current U.S. GAAP guidance on this topic and eliminated most industry-specific guidance. We adopted the guidance on January 1, 2018 applying the modified retrospective method.

Significant Accounting Polici_3

Significant Accounting Policies and Recent Accounting Standards (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Estimated Useful Lives of Property, Plant, and Equipment	Estimated useful lives of property, plant, and equipment are as follows: Estimated Useful Life Building and building equipment 10 to 35 years Machinery and equipment 2 to 15 years Capitalized software and internal-use software 3 to 5 years Leasehold improvements Lesser of useful life or lease term Film and media Revenue earned

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2020
Discontinued Operations And Disposal Groups [Abstract]
Summary of Amounts Included in Discontinued Operations	Selected financial information of the Riverside Business included in discontinued operations is as follows: For the Year Ended December 31, 2018 Net sales $ 56,562 Costs 37,714 Amortization 4,954 Earnings from discontinued operations before taxes 13,894 Income tax expense 1,061 Earnings from discontinued operations, net of tax $ 12,833

Balance Sheet Information (Tabl

Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accounts Receivable	Accounts receivable at December 31, 2020 and 2019 consisted of the following: 2020 2019 Accounts receivable $ 171,395 $ 204,119 Allowance for bad debt (3,989 ) (3,015 ) Reserve for book returns (14,574 ) (16,679 ) $ 152,832 $ 184,425
Schedule of Inventories	Inventories at December 31, 2020 and 2019 consisted of the following: 2020 2019 Finished goods $ 155,759 $ 203,103 Raw materials 11,204 9,956 Inventories $ 166,963 $ 213,059
Balances of Major Classes of Assets and Accumulated Depreciation and Amortization	Balances of major classes of assets and accumulated depreciation and amortization at December 31, 2020 and 2019 were as follows: 2020 2019 Land and land improvements $ 4,939 $ 4,939 Building and building equipment 11,160 10,239 Machinery and equipment 14,985 12,970 Capitalized software and internal-use software 641,027 598,317 Leasehold improvements 24,266 22,974 Film and media 29,845 22,055 726,222 671,494 Less: Accumulated depreciation and amortization (633,020 ) (571,106 ) Property, plant, and equipment, net $ 93,202 $ 100,388
Summary of Changes in Contract Assets and Contract Liabilities	The following table presents changes in contract assets and contract liabilities during the year ended December 31, 2020: December 31, December 31, 2020 2019 $ Change % Change Contract assets $ 580 $ 109 $ 471 432.11 % Contract liabilities (deferred revenue) $ 905,284 $ 848,106 $ 57,178 6.74 %
Summary of Net Sales Recognized from Changes in Contract Assets and Contract Liabilities	During the years ended December 31, 2020, 2019 and 2018, we recognized the following net sales as a result of changes in the contract assets and contract liabilities balances: Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Net sales recognized in the period from: Amounts included in contract liabilities at the beginning of the period $ 295,675 $ 229,557 $ 220,769

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Change in the Carrying Amount of Goodwill Relates to the Education Segment	The change in the carrying amount of goodwill, which all relates to the Education segment, for the year ended December 31, 2020 is as follows: Balance at December 31, 2019 $ 716,977 Impairment (279,000) Balance at December 31, 2020 $ 437,977
Schedule of Other Intangible Assets	Other intangible assets consisted of the following: December 31, 2020 December 31, 2019 Accumulated Accumulated Cost Amortization Total Cost Amortization Total Trademarks and tradenames: indefinite- Lived $ 161,000 $ — $ 161,000 $ 161,000 $ — $ 161,000 Trademarks and tradenames: definite- Lived 164,130 (53,610 ) 110,520 164,130 (38,948 ) 125,182 Publishing rights 1,180,000 (1,159,482 ) 20,518 1,180,000 (1,139,426 ) 40,574 Customer related and other 449,840 (313,294 ) 136,546 449,840 (302,371 ) 147,469 Other intangible assets, net $ 1,954,970 $ (1,526,386 ) $ 428,584 $ 1,954,970 $ (1,480,745 ) $ 474,225
Estimated Aggregate Amortization Expense Expected for Intangibles	Estimated aggregate amortization expense expected for each of the next five years related to intangibles subject to amortization is as follows: Trademarks Other and Publishing Intangible Tradenames Rights Assets 2021 14,408 11,642 10,333 2022 10,608 7,569 10,134 2023 6,808 1,307 9,954 2024 6,715 — 8,503 2025 6,437 8,315 Thereafter 65,544 — 89,307 $ 110,520 $ 20,518 $ 136,546

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Long-Term Debt	Our debt consisted of the following: December 31, December 31, 2020 2019 $380,000 term loan due November 22, 2024 interest payable quarterly (net of discount and issuance costs) $ 346,091 $ 361,294 $306,000 senior secured notes due February 15, 2025 interest payable semi-annually (net of discount and issuance costs) 297,601 295,893 643,692 657,187 Less: Current portion of long-term debt (19,000 ) (19,000 ) Total long-term debt, net of discount and issuance Costs $ 624,692 $ 638,187 Revolving credit facility $ — $ —
Long-Term Debt Repayments Due	Long-term debt repayments due in each of the next five years and thereafter is as follows: Year 2021 19,000 2022 19,000 2023 19,000 2024 304,000 2025 306,000 $ 667,000

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Schedule of Lease Assets and Liabilities	The table below presents the lease assets and liabilities recorded on the balance sheet. Leases Classification December 31, 2020 December 31, 2019 Assets Operating lease assets Operating lease assets $ 126,850 $ 132,247 Total leased assets $ 126,850 $ 132,247 Liabilities Current Operating Operating lease liabilities $ 9,669 $ 8,685 Noncurrent Operating Operating lease liabilities 132,014 134,994 Total lease liabilities $ 141,683 $ 143,679 Weighted average remaining lease term Operating leases 8.2 Years 9.6 Years Weighted average discount rate Operating leases (1) 12.56 % 12.46 % (1) Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019.
Summary of Undiscounted Cash Flows	The table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the operating lease liabilities recorded on the balance sheet. Operating Maturity of Lease Liabilities Leases 2021 24,143 2022 25,395 2023 27,838 2024 29,034 2025 28,370 Thereafter 110,993 Total lease payments $ 245,773 Less: interest (104,090 ) Present value of lease liabilities $ 141,683
Supplemental Cash Flow Information Related to Leases	The table below presents supplemental cash flow information related to leases during the years ended December 31, 2020 and 2019. Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases – 2020 $ 28,639 Operating cash flows for operating leases – 2019 $ 31,245

Restructuring, Severance and _2

Restructuring, Severance and Other Charges (Tables)	12 Months Ended
	Dec. 31, 2020
Components of Severance/Restructuring and Other Charges	A summary of the significant components of the severance costs, which are not allocated to our segments and instead are included in the Corporate and Other category, is as follows: 2020 Severance/ other accruals at December 2019 Severance/ other expense Cash payments Severance/ other accruals at December 31, 2020 Severance costs $ 758 $ — $ (758 ) $ — $ 758 $ — $ (758 ) $ — 2019 Severance/ Severance/ other other accruals at Severance/ accruals at December 31, other Cash December 31, 2018 expense payments 2019 Severance costs $ 1,420 $ 2,534 $ (3,196 ) $ 758 Other accruals 270 (1) — — — $ 1,690 $ 2,534 $ (3,196 ) $ 758 (1) A summary of the significant components of the severance/restructuring and other charges, which are not allocated to our segments and included in Corporate and Other, is as follows: 2018 Severance/ Severance/ other other accruals at Severance/ accruals at December 31, other Cash December 31, 2017 expense payments 2018 Severance costs $ 341 $ 6,821 $ (5,742 ) $ 1,420 Other accruals 1,299 — (1,029 ) 270 $ 1,640 $ 6,821 $ (6,771 ) $ 1,690
2020 Restructuring Plan [Member]
Components of Severance/Restructuring and Other Charges	The following table provides a summary of our total costs associated with the 2020 Restructuring Plan, included in the restructuring/severance and other charges line item within our consolidated statements of operations, for the year ended December 31, 2020, by major type of cost: Year Ended Total Amount December 31, Incurred Type of Cost 2020 to Date Restructuring charges: (1) Severance and termination benefits $ 33,643 $ 33,643 $ 33,643 $ 33,643 (1) All restructuring charges are included within Corporate and Other.
Summary of Restructuring Liabilities Comprised of Accruals for Severance and Termination Benefits	The following is a rollforward of our liabilities associated with the 2020 Restructuring Plan: 2020 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2019 Charges payments 2020 Severance and termination benefits $ — $ 33,643 $ (14,332) $ 19,311 $ — $ 33,643 $ (14,332) $ 19,311
2019 Restructuring Plan [Member]
Components of Severance/Restructuring and Other Charges	The following tables provide a summary of our total costs associated with the 2019 Restructuring Plan, included in the restructuring line item within our consolidated statements of operations, for the year ended December 31, 2019, by major type of cost: Year Ended Total Amount December 31, Incurred Type of Cost 2019 to Date Restructuring charges: (1) Severance and termination benefits $ 15,820 $ 15,820 $ 15,820 $ 15,820 (1) All restructuring charges are included within Corporate and Other.
Summary of Restructuring Liabilities Comprised of Accruals for Severance and Termination Benefits	The following is a rollforward of our liabilities associated with the 2019 Restructuring Plan: 2020 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2019 Charges payments 2020 Severance and termination benefits $ 11,649 $ — $ (11,370 ) $ 279 $ 11,649 $ — $ (11,370 ) $ 279 2019 Restructuring Restructuring accruals at accruals at December 31, Cash December 31, 2018 Charges payments 2019 Severance and termination benefits $ — $ 15,820 $ (4,171 ) $ 11,649 $ — $ 15,820 $ (4,171 ) $ 11,649

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Components of Loss Before Taxes by Jurisdiction	The components of loss before taxes by jurisdiction are as follows: For For For the Year the Year the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 U.S. $ (494,456 ) $ (213,541 ) $ (134,884 ) Foreign 2,214 3,909 3,024 Loss before taxes $ (492,242 ) $ (209,632 ) $ (131,860 )
Total Income Tax by Jurisdiction	Total income taxes by jurisdiction are as follows: For For For the Year the Year the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Income tax expense (benefit) U.S. $ (12,691 ) $ 4,273 $ 3,701 Foreign 287 (72 ) 1,896 $ (12,404 ) $ 4,201 $ 5,597
Components of (Benefit) Expense for Income Taxes Attributable to Loss from Continuing Operations	Significant components of the (benefit) expense for income taxes attributable to loss from continuing operations consist of the following: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Current Foreign $ 182 $ (730 ) $ 1,562 U.S.—Federal — 0 (63 ) U.S.—State and other 1,769 396 (1,042 ) Total current 1,951 (334 ) 457 Deferred Foreign 105 658 334 U.S.—Federal (5,505 ) 1,908 2,329 U.S.—State and other (8,955 ) 1,969 2,477 Total deferred (14,355 ) 4,535 5,140 Income tax (benefit) expense $ (12,404 ) $ 4,201 $ 5,597
Reconciliation of Income Tax Rate Computed at Statutory Tax Rate	The reconciliation of the income tax rate computed at the statutory tax rate to the reported income tax expense (benefit) attributable to continuing operations is as follows: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Statutory rate 21.0 % 21.0 % 21.0 % Permanent items (0.9 ) (3.6 ) (2.6 ) Foreign rate differential — — (0.1 ) State and local taxes 2.0 (7.9 ) 6.8 Cancellation of debt income — (1.3 ) — Increase in valuation allowance (15.5 ) (10.0 ) (26.6 ) Tax credits (0.2 ) (0.2 ) (2.7 ) Goodwill impairment (3.9 ) — — Effective tax rate 2.5 % (2.0 )% (4.2 )%
Components of Net Deferred Tax Assets and Liabilities	The significant components of the net deferred tax assets and liabilities are shown in the following table: 2020 2019 Tax assets related to Net operating loss and other carryforwards $ 326,504 $ 272,378 Returns reserve/inventory expense 39,095 41,824 Pension benefits 6,879 6,624 Postretirement benefits 4,480 4,475 Deferred interest (1) 226,227 259,375 Deferred revenue 141,775 113,029 Stock-based compensation 2,806 3,298 Deferred compensation 6,525 6,152 Research and development 12,435 10,302 Operating lease liabilities 33,963 35,890 Other, net 8,263 6,769 Valuation allowance (662,569 ) (583,505 ) $ 146,383 $ 176,611 2020 2019 Tax liabilities related to Indefinite-lived intangible assets (53,400 ) (89,879 ) Definite-lived intangible assets (21,578 ) (25,503 ) Depreciation and amortization expense (45,279 ) (48,984 ) Operating lease assets (30,245 ) (32,887 ) Other, net (9,877 ) (7,709 ) (160,379 ) (204,962 ) Net deferred tax liabilities $ (13,996 ) $ (28,351 ) ( 1 ) The deferred interest tax asset represents disallowed interest deductions under Section 163(j) (Limitation on Deduction for interest on Certain Indebtedness) of the Internal Revenue Code of 1986, as amended (“IRC”) for the current and prior years. At December 31, 2020 and 2019, we had gross deferred interest deductions totaling $900.2 million and $984.5 million, respectively. The disallowed interest is able to be carried forward indefinitely and utilized in future years pursuant to IRC Section 163(j). A full valuation allowance has been provided against deferred tax assets, excluding $2.4 million of foreign deferred tax assets which are expected to be realized, net of deferred tax liabilities resulting from indefinite-lived intangibles.
Deferred Tax Assets and Liabilities Reflected on Consolidated Balance Sheets	The net deferred tax liability balance is stated at prevailing statutory income tax rates. Deferred tax assets and liabilities are reflected on our consolidated balance sheets as follows: 2020 2019 Non-current deferred tax assets $ 2,415 $ 2,520 Non-current deferred tax liabilities (16,411 ) (30,871 ) $ (13,996 ) $ (28,351 )
Reconciliation of Gross Amount of Unrecognized Tax Benefits	A reconciliation of the gross amount of unrecognized tax benefits, excluding accrued interest and penalties, is as follows: Balance at December 31, 2017 $ 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2018 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2019 15,680 Reductions based on tax positions related to the prior year — Additions based on tax positions related to the prior year — Balance at December 31, 2020 $ 15,680

Retirement and Postretirement_2

Retirement and Postretirement Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2020
Summary of Accumulated Benefit Obligations Change in Projected Benefit Obligation and Funded Status of Plans	The following table summarizes the Accumulated Benefit Obligations (“ABO”), the change in Projected Benefit Obligation (“PBO”), and the funded status of our plans as of and for the financial statement period ended December 31, 2020 and 2019: 2020 2019 ABO at end of period $ 179,408 $ 169,364 Change in PBO PBO at beginning of period $ 169,364 $ 162,096 Interest cost on PBO 4,388 6,045 Plan settlements (4,990 ) — Actuarial loss (gain) 18,447 12,507 Benefits paid (7,801 ) (11,284 ) PBO at end of period $ 179,408 $ 169,364 Change in plan assets Fair market value at beginning of period $ 145,716 $ 132,776 Actual return 16,060 22,955 Company contribution 4,769 1,269 Plan settlements (4,990 ) — Benefits paid (7,801 ) (11,284 ) Fair market value at end of period $ 153,754 $ 145,716 Unfunded status $ (25,654 ) $ (23,648 )
Amounts Recognized in Consolidated Balance Sheets	Amounts recognized in the consolidated balance sheets at December 31, 2020 and 2019 consist of: 2020 2019 Current liabilities $ (1,593 ) $ — Noncurrent liabilities (24,061 ) (23,648 ) Net amount recognized $ (25,654 ) $ (23,648 )
Additional Year-End Information for Pension Plans with ABO in Excess of Plan Assets	Additional year-end information for pension plans with ABO in excess of plan assets at December 31, 2020 and 2019 consist of: 2020 2019 PBO $ 179,408 $ 169,364 ABO 179,408 169,364 Fair value of plan assets 153,754 145,716
Weighted Average Assumptions used to Determine Benefit Obligations	Weighted average assumptions used to determine the benefit obligations (both PBO and ABO) at December 31, 2020 and 2019 are: 2020 2019 Discount rate 2.2 % 3.1 % Increase in future compensation N/A N/A
Summary of Percentage of Assets Invested in Each Class	The percentage of assets invested in each asset class at December 31, 2020 and 2019 is shown below. 2020 2019 Percentage Percentage in Each in Each Asset Class Asset Class Asset Class Equity 33.5 % 32.6 % Fixed income 52.7 54.5 Real estate investment trust 7.0 8.0 Other 6.8 4.9 100.0 % 100.0 %
Summary of Fair Value of Pension Plan Assets by Asset Category	The fair value of our pension plan assets by asset category at December 31 were as follows: December 31, Not subject 2020 to leveling (1) Cash and cash equivalents $ 1,914 $ 1,914 Equity securities U.S. equity 27,765 27,765 Non-US equity 15,544 15,544 Emerging markets equity 8,259 8,259 Fixed income Government bonds 28,855 28,855 Corporate bonds 46,228 46,228 Mortgage-backed securities 9 9 Asset-backed securities 810 810 Commercial mortgage-backed securities 604 604 International fixed income 4,485 4,485 Alternatives Real estate 10,689 10,689 Hedge funds 8,228 8,228 Other 364 364 $ 153,754 $ 153,754 (1) Investments that are valued using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. December 31, Not subject 2019 to leveling (1) Cash and cash equivalents $ 1,413 $ 1,413 Equity securities U.S. equity 28,993 28,993 Non-US equity 12,474 12,474 Emerging markets equity 5,537 5,537 Fixed income Government bonds 20,316 20,316 Corporate bonds 37,925 37,925 Mortgage-backed securities 7,943 7,943 Asset-backed securities 3,255 3,255 Commercial mortgage-backed securities 1,930 1,930 International fixed income 5,741 5,741 Alternatives Real estate 11,609 11,609 Hedge funds 7,043 7,043 Other 1,537 1,537 $ 145,716 $ 145,716
Expected Future Benefit Payments	The following benefit payments, which reflect expected future service, are expected to be paid: Postretirement Fiscal Year Ended Benefit Plan 2021 $ 1,555 2022 1,488 2023 1,437 2024 1,389 2025 1,320 2026-2030 5,686
Summary of Accumulated Postretirement Benefit Obligation Changes in Plan Assets and Funded Status of Plan	The following table summarizes the Accumulated Postretirement Benefit Obligation (“APBO”), the changes in plan assets, and the funded status of our plan as of and for the financial statement periods ended December 31, 2020 and 2019. 2020 2019 Change in APBO APBO at beginning of period $ 16,684 $ 15,812 Service cost (benefits earned during the period) 67 58 Interest cost on APBO 426 582 Employee contributions 184 66 Actuarial loss (gain) 2,857 1,878 Benefits paid (2,097 ) (1,712 ) APBO at end of period $ 18,121 $ 16,684 Change in plan assets Fair market value at beginning of period $ — $ — Company contributions 1,913 1,646 Employee contributions 184 66 Benefits paid (2,097 ) (1,712 ) Fair market value at end of period $ — $ — Unfunded status $ (18,121 ) $ (16,684 )
Amounts not yet Reflected in Net Periodic Benefit Cost and Recognized in Accumulated Other Comprehensive (Loss) Income	2020 2019 Net (loss) gain $ (1,050 ) $ 1,771 Prior service cost (384 ) (426 ) Accumulated other comprehensive (loss) income $ (1,434 ) $ 1,345
One Percentage Point Changes in Assumed Health Care Cost	Assumed health care trend rates have a significant effect on the amounts reported for the health care plans. A one-percentage-point change in assumed health care cost trend rates would have the following effects on the expense recorded in 2020 and 2019 for the postretirement medical plan: 2020 2019 One-percentage-point increase Effect on total of service and interest cost components $ 2 $ 8 Effect on postretirement benefit obligation 87 85 One-percentage-point decrease Effect on total of service and interest cost components (2 ) (7 ) Effect on postretirement benefit obligation (77 ) (76 )
Summary of Change in Other Comprehensive Income	The following table presents the change in other comprehensive loss for the year ended December 31, 2020 related to our pension and postretirement obligations. Pension Postretirement Plans Benefit Plan Total Sources of change in accumulated other comprehensive loss Net loss arising during the period $ (9,807 ) $ (2,814 ) $ (12,621 ) Amortization of prior service credit — 42 42 Amortization of net gain (loss) 3,377 (7 ) 3,370 Total accumulated other comprehensive loss recognized during the period $ (6,430 ) $ (2,779 ) $ (9,209 )
Summary of Estimated Amounts Amortized from Accumulated Other Comprehensive Income (Loss) Over Next Fiscal Year	Estimated amounts that will be amortized from accumulated other comprehensive income (loss) over the next fiscal year. Pension Postretirement Plans Benefit Plan Prior service credit (cost) $ — $ (42 ) Net gain (loss) (3,389 ) — $ (3,389 ) $ (42 )
Pension Plans [Member]
Net Periodic Benefit Cost Components	Net periodic pension (income) cost includes the following components: For the For the For the Year Ended Year Ended Year Ended December 31, December 31, December 31, 2020 2019 2018 Interest cost on projected benefit obligation $ 4,388 $ 6,045 $ 5,300 Expected return on plan assets (7,419 ) (7,659 ) (7,985 ) Amortization of net loss 2,325 1,028 1,420 Settlement loss recognized 1,100 — — Net pension (income) expense recognized for the period $ 394 $ (586 ) $ (1,265 )
Significant Actuarial Assumptions used to Determine Net Periodic Pension Cost	Significant actuarial assumptions used to determine net periodic pension cost at December 31, 2020, 2019 and 2018 are: 2020 2019 2018 Discount rate 3.1 % 4.2 % 3.6 % Increase in future compensation N/A N/A N/A Expected long-term rate of return on assets 5.5 % 5.5 % 5.5 %
Expected Future Benefit Payments	The following benefit payments are expected to be paid. Fiscal Year Ended Pension 2021 $ 14,030 2022 12,817 2023 12,581 2024 12,789 2025 13,356 2026–2030 61,944
Other Post Retirement Plans [Member]
Amounts Recognized in Consolidated Balance Sheets	Amounts for postretirement benefits accrued in the consolidated balance sheets at December 31, 2020 and 2019 consist of: 2020 2019 Current liabilities $ (1,555 ) $ (1,571 ) Noncurrent liabilities (16,566 ) (15,113 ) Net amount recognized $ (18,121 ) $ (16,684 )
Weighted Average Assumptions used to Determine Benefit Obligations	Weighted average actuarial assumptions used to determine APBO at year-end December 31, 2020 and 2019 are: 2020 2019 Discount rate 2.2 % 3.1 % Health care cost trend rate assumed for next year 5.5 % 5.8 % Rate to which the cost trend rate is assumed to decline (ultimate trend rate) 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2038 2038
Net Periodic Benefit Cost Components	Net periodic postretirement benefit cost included the following components: 2020 2019 2018 Service cost $ 67 $ 58 $ 128 Interest cost on APBO 426 582 672 Amortization of unrecognized prior service cost 42 42 (690 ) Amortization of net (gain) loss (7 ) (164 ) — Net periodic postretirement benefit expense $ 528 $ 518 $ 110
Significant Actuarial Assumptions used to Determine Net Periodic Pension Cost	Significant actuarial assumptions used to determine postretirement benefit cost at December 31, 2020, 2019 and 2018 are: 2020 2019 2018 Discount rate 3.1 % 4.2 % 3.6 % Health care cost trend rate assumed for next year 5.8 % 6.1 % 6.3 % Rate to which the cost trend rate is assumed to decline (ultimate trend rate) 4.5 % 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2038 2038 2038
Amounts not yet Reflected in Net Periodic Benefit Cost and Recognized in Accumulated Other Comprehensive (Loss) Income	Amounts not yet reflected in net periodic benefit cost for pension plans and postretirement plan and recognized in accumulated other comprehensive income at December 31, 2020 and 2019 consist of: 2020 2019 Net actuarial loss $ (44,219 ) $ (35,010 ) Accumulated other comprehensive loss $ (44,219 ) $ (35,010 )

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Summary of Option Activity	The following table summarizes option activity for certain employees in our stock options: Weighted Number of Average Shares Exercise Price Balance at December 31, 2019 2,765,826 $ 13.10 Forfeited (868,614 ) 13.40 Balance at December 31, 2020 1,897,212 $ 12.95 Vested and expected to vest at December 31, 2020 1,883,100 $ 12.97 Exercisable at December 31, 2020 1,521,524 $ 13.65
Fair Value of Each Option Granted was Estimated on Grant Date using Black-Scholes Valuation Model	The fair value of each option granted was estimated on the grant date using the Black-Scholes valuation model with the following assumptions: For the Year Ended December 31, 2018 Expected term (years) (a) 4.75 Expected dividend yield 0.00% Expected volatility (b) 35.30% Risk-free interest rate (c) 2.84% (a) The expected term is the number of years that we estimate that options will be outstanding prior to exercise. During 2018, we have used the simplified method for estimating the expected term as we do not have sufficient stock option exercise experience to support a reasonable estimate of the expected term. The simplified method represents the best estimate of the expected term. (b) During 2018, we estimated volatility for options granted based on our historical volatility. (c) The risk-free interest rate is based on the U.S. Treasury yield for a period commensurate with the expected life of the option.
Summary of Restricted Stock Activity for Grants to Certain Executive Employees and Independent Members of Board of Directors	The following table summarizes restricted stock activity for grants to certain employees and independent members of the board of directors in our restricted stock units: Restricted Stock Units Weighted Average Numbers of Grant Date Units Fair Value Balance at December 31, 2019 3,846,608 $ 8.03 Granted 3,716,974 3.94 Vested (1,149,957 ) 8.50 Forfeited (723,816 ) 7.41 Balance at December 31, 2020 5,689,809 $ 5.34
Employees Stock Purchase Plan [Member]
Schedule of Share Repurchase Activity	Information related to shares issued or to be issued in connection with the ESPP based on employee contributions and the range of purchase prices is as follows: December 31, December 31, 2020 2019 Shares issued or to be issued 516,563 212,476 Range of purchase prices $1.54 - $1.56 $4.73 - $4.90

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present our financial assets and liabilities measured at fair value on a recurring basis at December 31, 2020 and 2019: Quoted Prices Significant in Active Other Markets for Observable Identical Assets Inputs Valuation 2020 (Level 1) (Level 2) Technique Financial assets Money market funds $ 262,135 $ 262,135 $ — (a) Foreign exchange derivatives 466 — 466 (a) $ 262,601 $ 262,135 $ 466 Quoted Prices Significant in Active Other Markets for Observable Identical Assets Inputs Valuation 2019 (Level 1) (Level 2) Technique Financial assets Money market funds $ 276,654 $ 276,654 $ — (a) $ 276,654 $ 276,654 $ — Financial liabilities Interest rate derivatives $ 986 $ — $ 986 (a) Foreign exchange derivatives 127 — 127 (a) $ 1,113 $ — $ 1,113
Summary of Non-financial Assets Measured at Fair Value on Nonrecurring Basis	The following table presents our nonfinancial assets measured at fair value on a nonrecurring basis during 2020: Significant Unobservable Inputs Total Valuation December 31, 2020 (Level 3) Impairment Technique Nonfinancial assets Goodwill $ 437,977 $ 437,977 $ 279,000 (c) $ 437,977 $ 437,977 $ 279,000
Summary of Carrying Amounts and Estimated Fair Market Values of Debt	The following table presents the carrying amounts and estimated fair market values of our debt at December 31, 2020 and 2019. The fair value of debt is deemed to be the amount at which the instrument could be exchanged in an orderly transaction between market participants at the measurement date. December 31, 2020 December 31, 2019 Carrying Estimated Carrying Estimated Amount Fair Value Amount Fair Value $380,000 Term loan $ 346,091 $ 331,382 $ 361,294 $ 360,391 $306,000 Senior secured notes 297,601 $ 304,297 295,893 301,441

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated other comprehensive loss consisted of the following at December 31, 2020, 2019 and 2018: 2020 2019 2018 Net change in pension and benefit plan liabilities $ (48,966 ) $ (39,757 ) $ (41,557 ) Foreign currency translation adjustments (6,650 ) (6,420 ) (5,909 ) Unrealized loss on short-term investments (90 ) (90 ) (99 ) Net change in unrealized loss on derivative instruments (18 ) (1,005 ) 2,381 $ (55,724 ) $ (47,272 ) $ (45,184 )

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings per Share	The following table sets forth the computation of basic and diluted earnings per share (“EPS”): For the Year For the Year For the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Numerator Loss from continuing operations $ (479,838 ) $ (213,833 ) $ (137,457 ) Earnings from discontinued operations, net of tax — — 12,833 Gain on sale of discontinued operations, net of tax — — 30,469 Income from discontinued operations, net of tax — — 43,302 Net loss attributable to common stockholders $ (479,838 ) $ (213,833 ) $ (94,155 ) Denominator Weighted average shares outstanding Basic and diluted 125,455,487 124,152,984 123,444,943 Net loss per share attributable to common Stockholders Basic and diluted: Continuing operations $ (3.82 ) $ (1.72 ) $ (1.11 ) Discontinued operations — — 0.35 Net loss $ (3.82 ) $ (1.72 ) $ (0.76 )
Summary of Anti-Dilutive Securities Excluded from Computation of Diluted EPS	The following table summarizes our weighted average outstanding common stock equivalents that were anti-dilutive attributable to common stockholders during the periods, and therefore excluded from the computation of diluted EPS: For the Year For the Year For the Year Ended Ended Ended December 31, December 31, December 31, 2020 2019 2018 Stock options 1,897,212 2,765,826 3,406,171 Restricted stock units 4,133,531 3,342,923 2,793,680

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Consolidated Net Income (Loss)	Although we exclude these amounts from segment Adjusted EBITDA from continuing operations, they are included in reported consolidated net loss and are included in the reconciliation below. Year Ended December 31, HMH Corporate/ (in thousands) Education Books & Media Other 2020 Net sales $ 839,553 $ 191,739 $ — Segment Adjusted EBITDA 145,862 26,627 (40,649 ) 2019 Net sales $ 1,210,646 $ 180,028 $ — Segment Adjusted EBITDA 196,907 14,908 (46,077 ) 2018 Net sales $ 1,122,689 $ 199,728 $ — Segment Adjusted EBITDA 210,604 21,942 (40,418 )
Summary of Net Sales	The following table disaggregates our net sales by major source: Year Ended December 31, 2020 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 459,350 $ — $ 459,350 Extensions businesses (2) 380,203 — 380,203 Books & Media — 191,739 191,739 Net sales $ 839,553 $ 191,739 $ 1,031,292 Year Ended December 31, 2019 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 578,675 $ — $ 578,675 Extensions businesses (2) 631,971 — 631,971 Books & Media — 180,028 180,028 Net sales $ 1,210,646 $ 180,028 $ 1,390,674 Year Ended December 31, 2018 HMH (in thousands) Education Books & Media Consolidated Core solutions (1) $ 538,166 $ — $ 538,166 Extensions businesses (2) 584,523 — 584,523 Books & Media — 199,728 199,728 Net sales $ 1,122,689 $ 199,728 $ 1,322,417 (1) Comprehensive solutions primarily for reading, literature, math, science and social studies programs. (2) Primarily consists of our Heinemann brand, intervention, supplemental and professional services.
Consolidated Statements of Operations	Reconciliation of Segment Adjusted EBITDA to the consolidated statements of operations is as follows: Years Ended December 31, (in thousands) 2020 2019 2018 Education Adjusted EBITDA $ 145,862 $ 196,907 $ 210,604 HMH Books & Media Adjusted EBITDA 26,627 14,908 21,942 Total Segment Adjusted EBITDA 172,489 211,815 232,546 Corporate/Other Adjusted EBITDA (40,649 ) (46,077 ) (40,418 ) Interest expense (65,959 ) (48,778 ) (45,680 ) Interest income 899 3,157 2,550 Depreciation expense (50,715 ) (61,475 ) (75,116 ) Amortization expense—film asset (13,953 ) (9,835 ) (6,057 ) Amortization expense (171,821 ) (201,382 ) (170,903 ) Non-cash charges—stock compensation (11,573 ) (13,968 ) (13,248 ) Non-cash charges—loss on derivative instruments 672 (899 ) (1,374 ) Non-cash charges—asset impairment charges (279,000 ) — — Inventory obsolescence related to strategic transformation plan — (9,758 ) — Fees, expenses or charges for equity offerings, debt or acquisitions/dispositions (1,080 ) (6,327 ) (2,883 ) Restructuring/severance and other charges (33,643 ) (21,742 ) (11,478 ) Gain on investments 2,091 — — Gain on sale of assets — — 201 Loss on extinguishment of debt — (4,363 ) — Loss before taxes (492,242 ) (209,632 ) (131,860 ) (Provision) benefit for income taxes 12,404 (4,201 ) (5,597 ) Net loss from continuing operations $ (479,838 ) $ (213,833 ) $ (137,457 )
Segment Information	Segment information as of December 31, 2020 and 2019 is as follows: (in thousands) 2020 2019 Total assets—Education segment $ 1,520,504 $ 1,971,553 Total assets—HMH Books & Media segment 175,710 186,318 Total assets—Corporate and Other 324,912 355,301 Total consolidated assets $ 2,021,126 $ 2,513,172
Schedule of Long-Lived Assets	The following represents long-lived assets (property, plant, and equipment) outside of the United States, which are substantially in Ireland. All other long-lived assets are located in the United States. (in thousands) 2020 2019 Long-lived assets—International $ 228 $ 113
Schedule of Net Sales by Geographic Region	The following is a schedule of net sales by geographic region: (in thousands) Year Ended December 31, 2020 Net sales—U.S. $ 997,178 Net sales—International 34,114 Total net sales $ 1,031,292 Year Ended December 31, 2019 Net sales—U.S. $ 1,327,833 Net sales—International 62,841 Total net sales $ 1,390,674 Year Ended December 31, 2018 Net sales—U.S. $ 1,249,568 Net sales—International 72,849 Total net sales $ 1,322,417

Valuation and Qualifying Acco_2

Valuation and Qualifying Accounts (Tables)	12 Months Ended
	Dec. 31, 2020
Valuation And Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	Balance at Balance at Beginning Utilization of End of Year Net Charges Allowances of Year 2020 Allowance for doubtful accounts $ 3,015 $ 1,589 $ (615 ) $ 3,989 Reserve for returns 16,679 33,847 (35,952 ) 14,574 Reserve for royalty advances 119,695 16,552 (39,592 ) 96,655 Deferred tax valuation allowance 583,505 81,475 (2,412 ) 662,568 2019 Allowance for doubtful accounts $ 2,173 $ 1,909 $ (1,067 ) $ 3,015 Reserve for returns 18,559 41,654 (43,534 ) 16,679 Reserve for royalty advances 117,797 16,500 (14,602 ) 119,695 Deferred tax valuation allowance 562,392 23,707 (2,594 ) 583,505 2018 Allowance for doubtful accounts $ 2,508 $ 128 $ (463 ) $ 2,173 Reserve for returns 20,580 36,395 (38,416 ) 18,559 Reserve for royalty advances 103,606 17,301 (3,110 ) 117,797 Deferred tax valuation allowance 571,653 (7,667 ) (1,594 ) 562,392

Quarterly Results of Operatio_2

Quarterly Results of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Results of Operations	Three Months Ended March 31, June 30, September 30, December 31, 2020: Net sales $ 189,925 $ 251,216 $ 386,590 $ 203,561 Gross profit 63,450 90,389 167,415 65,986 Operating (loss) income (338,176 ) (22,212 ) 272 (68,973 ) Net loss (345,973 ) (38,168 ) (12,552 ) (83,145 ) Net loss per share attributable to common stockholders Basic: Net loss $ (2.77 ) $ (0.30 ) $ (0.10 ) $ (0.66 ) Diluted: Net loss $ (2.77 ) $ (0.30 ) $ (0.10 ) $ (0.66 ) 2019: Net sales $ 194,635 $ 388,896 $ 565,668 $ 241,475 Gross profit 57,893 156,055 273,481 59,065 Operating (loss) income (101,835 ) (30,253 ) 77,871 (108,947 ) Net (loss) income (117,362 ) (40,613 ) 69,260 (125,118 ) Net (loss) income per share attributable to common stockholders Basic: Net (loss) income $ (0.95 ) $ (0.33 ) $ 0.56 $ (1.01 ) Diluted: Net (loss) income $ (0.95 ) $ (0.33 ) $ 0.55 $ (1.01 )

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) Student in Millions, Educator in Millions	12 Months Ended
	Dec. 31, 2020StudentCountryEducatorSegment	Dec. 31, 2019	Dec. 31, 2018
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Services provided, number of students | Student	50
Services provided, number of countries | Country	150
Services provided, number of educators | Educator	3
Number of business segments | Segment	2
Seasonal Concentration Risk [Member] | Consolidated Net Sales [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Consolidated net sales, realized percentage	66.00%	66.00%	66.00%
Seasonal Concentration Risk [Member] | Consolidated Net Sales [Member] | Education [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Consolidated net sales, realized percentage	81.00%

Impact of the COVID-19 Pandem_2

Impact of the COVID-19 Pandemic - Additional Information (Detail)	Sep. 30, 2020USD ($)Employee	Sep. 04, 2020Employee	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Oct. 01, 2019
Unusual Or Infrequent Item [Line Items]
Goodwill impairment				$ 0	$ 262,000,000	$ 279,000,000	$ 0	$ 0
Percentage of fair value in excess of carrying value	18.00%			18.00%	12.00%				18.00%
Goodwill Impairment Charge [Member]
Unusual Or Infrequent Item [Line Items]
Prior period correction amounts			$ 17,000,000
Income Tax Benefit [Member]
Unusual Or Infrequent Item [Line Items]
Prior period correction amounts			$ 1,000,000
2020 Restructuring Plan [Member]
Unusual Or Infrequent Item [Line Items]
Restructuring program, positions eliminated percentage	22.00%
Restructuring program, number of positions eliminated | Employee	525
Restructuring program, cash expenditure	$ 33,600,000					$ 758,000
Restructuring program, completion month and year	2020-10
Retirement Incentive Program [Member] | 2020 Restructuring Plan [Member]
Unusual Or Infrequent Item [Line Items]
Minimum eligible age of employees to offer voluntary retirement program		55 years
Minimum years of employee service to offer voluntary retirement program		5 years
Number of employees eligible to participate in voluntary retirement program | Employee		165
Percentage of employee base, eligible to participate in voluntary retirement program		5.00%

Significant Accounting Polici_4

Significant Accounting Policies and Recent Accounting Standards - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 01, 2019
Significant Accounting Policies [Line Items]
Advertising costs			$ 12,100,000	$ 12,600,000	$ 12,000,000
Impairment charges			279,000,000
Percentage of fair value of education reporting unit in excess of carrying value	18.00%	12.00%				18.00%
Goodwill impairment	$ 0	$ 262,000,000	279,000,000	0	0
Impairment of intangible assets			0	0	0
Impairment charges relating to goodwill and intangibles			0	0	0
Operating lease, asset			126,850,000	132,247,000
Operating lease, liability			141,683,000	143,679,000
Adjustment to accumulated deficit			(4,255,830,000)	(3,775,992,000)
Net change in unrealized gain (loss) on derivative financial instruments, net of tax			987,000	(3,386,000)	3,541,000
Allowance for doubtful accounts			4,000,000	3,000,000
Increase in allowance for doubtful accounts			1,600,000
Allowance for doubtful accounts, write-offs			600,000
Reserve balance			96,700,000	119,700,000
Decrease in advance royalties reserve			$ 23,000,000
Interest Rate Hedging [Member]
Significant Accounting Policies [Line Items]
Net change in unrealized gain (loss) on derivative financial instruments, net of tax				(3,400,000)	3,500,000
Total hedge liability included within current other liabilities				1,000,000
Derivative contracts maturity date			Jul. 22, 2020
Accounting Standards Update 2016-02 [Member]
Significant Accounting Policies [Line Items]
Operating lease, asset			$ 148,000,000
Operating lease, liability			161,000,000
Accounting Standards Update 2016-02 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Significant Accounting Policies [Line Items]
Adjustment to accumulated deficit			$ 800,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Acquired publication rights and customer-related intangibles, amortization period			3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Acquired publication rights and customer-related intangibles, amortization period			20 years
Pre-publication Costs [Member]
Significant Accounting Policies [Line Items]
Impairment charges			$ 0	0	0
Amortization expense for pre-publication cost, year 1			33.00%
Amortization expense for pre-publication cost, year 2			27.00%
Amortization expense for pre-publication cost, year 3			20.00%
Amortization expense for pre-publication cost, year 4			13.00%
Amortization expense for pre-publication cost, year 5			7.00%
Amortization period of acquisition costs			7 years
Amortization of intangible assets, cost of sales			$ 126,200,000	149,500,000	109,300,000
Software Developments Costs [Member]
Significant Accounting Policies [Line Items]
Impairment charges			$ 0	$ 0	$ 0

Significant Accounting Polici_5

Significant Accounting Policies and Recent Accounting Standards - Summary of Estimated Useful Lives of Property, Plant, and Equipment (Detail)	12 Months Ended
	Dec. 31, 2020
Building and Building Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	10 years
Building and Building Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	35 years
Machinery and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	2 years
Machinery and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	15 years
Capitalized Software and Internal-use Software [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	3 years
Capitalized Software and Internal-use Software [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	5 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	Lesser of useful life or lease term
Film and Media [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	Revenue earned

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands	Jan. 14, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill		$ 437,977	$ 716,977
PV Waggle LLC [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price	$ 5,400
Other liabilities	700
Other intangible assets	5,200
Goodwill	$ 900

Discontinued Operations - Addit

Discontinued Operations - Additional Information (Detail) - USD ($)	Oct. 02, 2018	Sep. 12, 2018	Dec. 31, 2018	Dec. 31, 2018	Oct. 01, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of business				$ 140,000,000
Riverside Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration received					$ 140,000,000
Proceeds from sale of business	$ 135,000,000
Gain on sale of business			$ 30,500,000
Goodwill		$ 67,000,000
Goodwill impairment, discontinued operation		$ 0

Discontinued Operations - Summa

Discontinued Operations - Summary of Amounts Included in Discontinued Operations (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of tax	$ 43,302
Riverside Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	56,562
Costs	37,714
Amortization	4,954
Earnings from discontinued operations before taxes	13,894
Income tax expense	1,061
Income from discontinued operations, net of tax	$ 12,833

Balance Sheet Information - Acc

Balance Sheet Information - Accounts Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable [Line Items]
Accounts receivable	$ 171,395	$ 204,119
Allowance for bad debt	(4,000)	(3,000)
Accounts Receivable, Net, Total	152,832	184,425
Allowance for Bad Debt [Member]
Accounts Receivable [Line Items]
Allowance for bad debt	(3,989)	(3,015)
Reserve for Book Returns [Member]
Accounts Receivable [Line Items]
Allowance for bad debt	$ (14,574)	$ (16,679)

Balance Sheet Information - Add

Balance Sheet Information - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Details [Line Items]
Depreciation	$ 50,715	$ 61,475	$ 75,116
Property, plant, and equipment acquired under finance lease agreements	100	300
Amortization expense	20,056	26,557	34,713
Increase in net contract liabilities from increase in contract liabilities	56,700
Aggregate amount of transaction price allocated to remaining performance obligations	$ 970,300
Percentage of transaction recognized	73.00%
Deferred commissions	$ 30,659	29,291
Amortization of deferred commissions	12,900	13,200	10,500
Contract cost	14,700	5,600
Amortization contract cost	$ 3,800	4,600
Minimum [Member]
Balance Sheet Details [Line Items]
Period of duration for recognition of transaction	1 year
Maximum [Member]
Balance Sheet Details [Line Items]
Period of duration for recognition of transaction	3 years
Film and Media [Member]
Balance Sheet Details [Line Items]
Amortization expense	$ 14,000	9,800	6,100
Property, Plant, and Equipment [Member]
Balance Sheet Details [Line Items]
Depreciation	64,700	$ 71,300	$ 81,200
Capital leases 2021	$ 100
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Balance Sheet Details [Line Items]
Concentration Risk, percentage	10.00%	10.00%

Balance Sheet Information - Sch

Balance Sheet Information - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Finished goods	$ 155,759	$ 203,103
Raw materials	11,204	9,956
Inventories	$ 166,963	$ 213,059

Balance Sheet Information - Bal

Balance Sheet Information - Balances of Major Classes of Assets and Accumulated Depreciation and Amortization (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Offsetting [Abstract]
Land and land improvements	$ 4,939	$ 4,939
Building and building equipment	11,160	10,239
Machinery and equipment	14,985	12,970
Capitalized software and internal-use software	641,027	598,317
Leasehold improvements	24,266	22,974
Film and media	29,845	22,055
Property, Plant and Equipment, Gross, Total	726,222	671,494
Less: Accumulated depreciation and amortization	(633,020)	(571,106)
Property, plant, and equipment, net	$ 93,202	$ 100,388

Balance Sheet Information - Sum

Balance Sheet Information - Summary of Changes in Contract Assets and Contract Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investments Debt And Equity Securities [Abstract]
Contract with customer assets	$ 580	$ 109
Contract with customer liabilities	905,284	$ 848,106
Contract with customer assets change	471
Contract with customer liabilities change	$ 57,178
Contract with customer assets percentage change	432.11%
Contract with customer liabilities percentage change	6.74%

Balance Sheet Information - S_2

Balance Sheet Information - Summary of Net Sales Recognised from Changes in Contract Assets and Contract Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net sales recognized in the period from:
Amounts included in contract liabilities at the beginning of the period	$ 295,675	$ 229,557	$ 220,769

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Schedule of Change in the Carrying Amount of Goodwill Relates to the Education Segment (Details) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at December 31, 2019		$ 716,977,000	$ 716,977,000
Impairment	$ 0	$ (262,000,000)	(279,000,000)	$ 0	$ 0
Balance at December 31, 2020			$ 437,977,000	$ 716,977,000

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Other Intangible Assets [Line Items]
Accumulated impairment losses on goodwill			$ 279,000,000
Impairment charge for goodwill	$ 0	$ 262,000,000	279,000,000	$ 0	$ 0
Amortization expense			20,056,000	26,557,000	34,713,000
Definite-lived, Publishing Rights and Customer Related and Other Intangibles [Member]
Goodwill and Other Intangible Assets [Line Items]
Amortization expense			$ 45,600,000	51,900,000	$ 61,600,000
PV Waggle LLC [Member]
Goodwill and Other Intangible Assets [Line Items]
Intangible asset recorded on acquisition				$ 5,200,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Other Intangible Assets [Line Items]
Cost	$ 1,954,970	$ 1,954,970
Accumulated Amortization	(1,526,386)	(1,480,745)
Total	428,584	474,225
Trademarks and Trade Names [Member]
Goodwill and Other Intangible Assets [Line Items]
Trademarks and tradenames: indefinite-Lived	161,000	161,000
Cost	164,130	164,130
Accumulated Amortization	(53,610)	(38,948)
Total	110,520	125,182
Publishing Rights [Member]
Goodwill and Other Intangible Assets [Line Items]
Cost	1,180,000	1,180,000
Accumulated Amortization	(1,159,482)	(1,139,426)
Total	20,518	40,574
Customer Related and Other [Member]
Goodwill and Other Intangible Assets [Line Items]
Cost	449,840	449,840
Accumulated Amortization	(313,294)	(302,371)
Total	$ 136,546	$ 147,469

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets - Estimated Aggregate Amortization Expense (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Trademarks and Trade Names [Member]
Goodwill and Other Intangible Assets [Line Items]
2021	$ 14,408
2022	10,608
2023	6,808
2024	6,715
2025	6,437
Thereafter	65,544
Total	110,520	$ 125,182
Publishing Rights [Member]
Goodwill and Other Intangible Assets [Line Items]
2021	11,642
2022	7,569
2023	1,307
Total	20,518	$ 40,574
Other Intangible Assets [Member]
Goodwill and Other Intangible Assets [Line Items]
2021	10,333
2022	10,134
2023	9,954
2024	8,503
2025	8,315
Thereafter	89,307
Total	$ 136,546

Debt - Long-Term Debt (Detail)

Debt - Long-Term Debt (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long term debt	$ 643,692,000	$ 657,187,000
Less: Current portion of long-term debt	(19,000,000)	(19,000,000)
Total long-term debt, net of discount and issuance Costs	624,692,000	638,187,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility	0
Term Loan Due November 22, 2024 [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Long term debt	346,091,000	361,294,000
Senior Secured Notes Due February 15, 2025 [Member] | Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 297,601,000	$ 295,893,000

Debt - Long-Term Debt (Parenthe

Debt - Long-Term Debt (Parenthetical) (Detail) - USD ($) $ in Thousands	Nov. 22, 2019	Dec. 31, 2020	Dec. 31, 2019
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Term loan, face amount	$ 306,000
Term loan, due date	Feb. 15, 2025
Term Loan Due November 22, 2024 [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Term loan, face amount	$ 380,000	$ 380,000	$ 380,000
Term loan, due date	Nov. 22, 2024	Nov. 22, 2024	Nov. 22, 2024
Senior Secured Notes Due February 15, 2025 [Member] | Senior Secured Notes [Member]
Debt Instrument [Line Items]
Term loan, face amount		$ 306,000	$ 306,000
Term loan, due date		Feb. 15, 2025	Feb. 15, 2025

Debt - Long - Term Debt Repayme

Debt - Long - Term Debt Repayments Due (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Equity Method Investments And Cost Method Investments [Abstract]
2021	$ 19,000
2022	19,000
2023	19,000
2024	304,000
2025	306,000
Long-term debt repayments amount	$ 667,000

Debt - Additional Information (

Debt - Additional Information (Detail)	Nov. 22, 2019USD ($)	Jul. 22, 2015	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Aug. 17, 2015USD ($)
Debt Instrument [Line Items]
Debt outstanding amount			$ 667,000,000
Loss on extinguishment of debt				$ (4,363,000)
Net change in unrealized gain (loss) on derivative financial instruments			987,000	(3,386,000)	$ 3,541,000
Reclassified from other comprehensive loss to earnings			1,900,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Deferred financing fees, net	$ 1,100,000
Revolving Credit Facility, maximum borrowing capacity	250,000,000
Revolving Credit Facility, outstanding			$ 0
Financial covenants, description			As of December 31, 2020, the minimum fixed charge coverage ratio covenant under our revolving credit facility was not applicable, due to our level of borrowing availability. The minimum fixed charge coverage ratio, which is only tested in limited situations, is 1.0 to 1.0 through the end of the facility.
Revolving Credit Facility [Member] | Letter Of Credit Subfacility [Member]
Debt Instrument [Line Items]
Revolving Credit Facility, current capacity	50,000,000
Revolving Credit Facility [Member] | Swingline [Member]
Debt Instrument [Line Items]
Revolving Credit Facility, current capacity	20,000,000
Revolving Credit Facility [Member] | Subfacility [Member]
Debt Instrument [Line Items]
Revolving Credit Facility, maximum borrowing capacity	100,000,000
Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio		1	1
Interest Rate Hedging [Member]
Debt Instrument [Line Items]
Aggregate notional amount of derivative instruments						$ 400,000,000
Net change in unrealized gain (loss) on derivative financial instruments				(3,400,000)	$ 3,500,000
Total hedge liability included within current other liabilities				1,000,000
Interest rate derivative contracts outstanding			$ 0
Interest Rate Hedging [Member] | Maximum [Member]
Debt Instrument [Line Items]
Unrealized gain (loss) on interest rate derivative instruments			$ 100,000	100,000
Interest Rate Hedging [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument
Debt Instrument [Line Items]
Aggregate notional amount of derivative instruments	29,500,000
Interest Rate Hedging [Member] | Cash Flow Hedging [Member] | Not Designated as Hedging Instrument
Debt Instrument [Line Items]
Aggregate notional amount of derivative instruments	29,500,000
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Term loan, face amount	$ 306,000,000
Debt instrument, interest rate, stated percentage	9.00%
Term loan, due date	Feb. 15, 2025
Debt instrument basis spread	9.00%
Repayment frequency			Interest is payable semi-annually in arrears on February 15 and August 15 of each year, beginning on February 15, 2020
Deferred financing fees				5,400,000
Deferred financing fees, net				4,100,000
Senior Secured Notes [Member] | Selling, General and Administrative Expenses [Member]
Debt Instrument [Line Items]
Deferred financing expense				1,300,000
Senior Secured Notes [Member] | Senior Secured Notes Due February 15, 2025 [Member]
Debt Instrument [Line Items]
Term loan, face amount			$ 306,000,000	$ 306,000,000
Term loan, due date			Feb. 15, 2025	Feb. 15, 2025
Percentage of outstanding borrowing commitment issued as discount			2.00%
Term Loan Facility [Member]
Debt Instrument [Line Items]
Deferred financing fees				$ 7,200,000
Deferred financing fees, net				2,900,000
Percentage of principal for subject to prepayment premium			1.00%
Debt outstanding amount	$ 800,000,000
Loss on extinguishment of debt	4,400,000
Term Loan Facility [Member] | Selling, General and Administrative Expenses [Member]
Debt Instrument [Line Items]
Deferred financing expense				4,300,000
Term Loan Facility [Member] | Term Loan Due November 22, 2024 [Member]
Debt Instrument [Line Items]
Term loan, face amount	$ 380,000,000		$ 380,000,000	$ 380,000,000
Term loan, due date	Nov. 22, 2024		Nov. 22, 2024	Nov. 22, 2024
Debt instrument basis spread			7.25%
Percentage of outstanding borrowing commitment issued as discount			4.00%
Amount to be repaid quarterly	$ 4,800
Term Loan Facility [Member] | Term Loan Due November 22, 2024 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument basis spread	6.25%
Term Loan Facility [Member] | Term Loan Due November 22, 2024 [Member] | Alternate Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument basis spread	5.25%

Leases - Schedule of Lease Asse

Leases - Schedule of Lease Assets and Liabilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Leases Assets
Operating lease assets		$ 126,850	$ 132,247
Total leased assets		126,850	132,247
Current
Operating lease liabilities		9,669	8,685
Noncurrent
Operating lease liabilities		132,014	134,994
Total lease liabilities		$ 141,683	$ 143,679
Weighted average remaining lease term Operating leases		8 years 2 months 12 days	9 years 7 months 6 days
Weighted average discount rate Operating leases	[1]	12.56%	12.46%
[1]	Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019.

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Operating Lease, Cost		$ 34.9	$ 39.9
Sublease Income		2.1	2.3
Lease term	10 years
Option to renew additional years	5 years
Estimated fixed lease payments	$ 9.8
Selling, General and Administrative Expenses [Member]
Lease, Cost		$ 32.8	$ 37.6

Leases - Summary of Undiscounte

Leases - Summary of Undiscounted Cash Flows (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
2021	$ 24,143
2022	25,395
2023	27,838
2024	29,034
2025	28,370
Thereafter	110,993
Total lease payments	245,773
Less: interest	(104,090)
Present value of lease liabilities	$ 141,683	$ 143,679

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Cash paid for amounts included in the measurement of lease liabilities Operating cash flows for operating leases	$ 28,639	$ 31,245

Restructuring, Severance and _3

Restructuring, Severance and Other Charges - Additional Information (Detail) $ in Thousands

Sep. 30, 2020USD ($)Employee

Sep. 04, 2020Employee

Oct. 15, 2019

Dec. 31, 2019USD ($)

Dec. 31, 2019USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2020USD ($)

Dec. 31, 2019USD ($)

Dec. 31, 2018USD ($)

Restructuring Cost and Reserve [Line Items]

Restructuring/severance and other charges

$ 33,643

$ 21,742

$ 11,478

Severance and other charges

$ 12,400

$ 12,400

$ 19,600

19,600

12,400

Operating Lease Assets [Member]

Restructuring Cost and Reserve [Line Items]

Restructuring costs

3,400

Severance Costs [Member]

Restructuring Cost and Reserve [Line Items]

Payments for severance cost

800

3,200

5,700

Restructuring/severance and other charges

2,500

6,800

Other Accruals [Member]

Restructuring Cost and Reserve [Line Items]

Payments for severance cost

$ 1,000

2020 Restructuring Plan [Member]

Restructuring Cost and Reserve [Line Items]

Restructuring program, positions eliminated percentage

22.00%

Restructuring program, number of positions eliminated | Employee

525

Restructuring program, completion month and year

2020-10

Payments for severance cost

$ 33,600

758

Restructuring/severance and other charges

[1]

$ 33,643

33,643

2020 Restructuring Plan [Member] | Severance Costs [Member]

Restructuring Cost and Reserve [Line Items]

Payments for severance cost

758

2020 Restructuring Plan [Member] | Retirement Incentive Program [Member]

Restructuring Cost and Reserve [Line Items]

Minimum eligible age of employees to offer voluntary retirement program

55 years

Minimum years of employee service to offer voluntary retirement program

5 years

Number of employees eligible to participate in voluntary retirement program | Employee

165

Percentage of employee base, eligible to participate in voluntary retirement program

5.00%

2019 Restructuring Plan [Member]

Restructuring Cost and Reserve [Line Items]

Restructuring program, positions eliminated percentage

10.00%

Payments for severance cost

$ 3,196

Percentage of reduction in content development expenditures

20.00%

Description of workforce reduction

The workforce reductions were completed in the first quarter of 2020.

Restructuring/severance and other charges

$ 15,800

$ 15,820

[1]

$ 15,820

[1]

2019 Restructuring Plan [Member] | Severance Costs [Member]

Restructuring Cost and Reserve [Line Items]

Payments for severance cost

$ 3,196

2019 Restructuring Plan [Member] | Cost of Sales [Member]

Restructuring Cost and Reserve [Line Items]

Inventory obsolescence charge

$ 9,800

[1]

All restructuring charges are included within Corporate and Other.

Restructuring, Severance and _4

Restructuring, Severance and Other Charges - Summary of Restructuring/Severance Total Costs (Detail) - USD ($) $ in Thousands		3 Months Ended			4 Months Ended	12 Months Ended
		Dec. 31, 2019	Dec. 31, 2019		Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019		Dec. 31, 2018
Condensed Comprehensive Income [Line Items]
Restructuring charges						$ 33,643	$ 21,742		$ 11,478
2020 Restructuring Plan [Member]
Condensed Comprehensive Income [Line Items]
Restructuring charges	[1]				$ 33,643	33,643
2020 Restructuring Plan [Member] | Severance and Termination Benefits [Member]
Condensed Comprehensive Income [Line Items]
Restructuring charges	[1]				$ 33,643	$ 33,643
2019 Restructuring Plan [Member]
Condensed Comprehensive Income [Line Items]
Restructuring charges		$ 15,800	$ 15,820	[1]			15,820	[1]
2019 Restructuring Plan [Member] | Severance and Termination Benefits [Member]
Condensed Comprehensive Income [Line Items]
Restructuring charges	[1]		$ 15,820				$ 15,820
[1]	All restructuring charges are included within Corporate and Other.

Restructuring, Severance and _5

Restructuring, Severance and Other Charges - Summary of Restructuring Liabilities Comprised of Accruals for Severance and Termination Benefits (Detail) - USD ($) $ in Thousands		Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2019		Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019		Dec. 31, 2018
Condensed Comprehensive Income [Line Items]
Charges							$ 33,643	$ 21,742		$ 11,478
2020 Restructuring Plan [Member]
Condensed Comprehensive Income [Line Items]
Severance/restructuring and other accruals, Beginning balance							758
Charges	[1]					$ 33,643	33,643
Cash payments		$ (33,600)					(758)
Severance/restructuring and other accruals, Ending balance			$ 758	$ 758				758
2020 Restructuring Plan [Member] | Severance and Termination Benefits [Member]
Condensed Comprehensive Income [Line Items]
Charges	[1]					33,643	33,643
Cash payments							(14,332)
Severance/restructuring and other accruals, Ending balance						19,311	19,311
2019 Restructuring Plan [Member]
Condensed Comprehensive Income [Line Items]
Severance/restructuring and other accruals, Beginning balance							1,690
Charges			15,800	15,820	[1]			15,820	[1]
Cash payments							(3,196)
Severance/restructuring and other accruals, Ending balance			1,690	1,690		758	758	1,690
2019 Restructuring Plan [Member] | Severance and Termination Benefits [Member]
Condensed Comprehensive Income [Line Items]
Severance/restructuring and other accruals, Beginning balance							11,649
Charges	[1]			15,820				15,820
Cash payments							(11,370)	(4,171)
Severance/restructuring and other accruals, Ending balance			$ 11,649	$ 11,649		$ 279	$ 279	$ 11,649
[1]	All restructuring charges are included within Corporate and Other.

Restructuring, Severance and _6

Restructuring, Severance and Other Charges - Components of Severance/Restructuring and Other Charges (Detail) - USD ($) $ in Thousands		Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Severance Costs [Member]
Restructuring Cost and Reserve [Line Items]
Cash payments			$ (800)	$ (3,200)	$ (5,700)
Other Accruals [Member]
Restructuring Cost and Reserve [Line Items]
Cash payments					(1,000)
2020 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance			758
Cash payments		$ (33,600)	(758)
Severance/restructuring and other accruals, Ending balance				758
2020 Restructuring Plan [Member] | Severance Costs [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance			758
Cash payments			(758)
Severance/restructuring and other accruals, Ending balance				758
2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance			1,690
Severance/other expense			2,534
Cash payments			(3,196)
Severance/restructuring and other accruals, Ending balance			758	1,690
2019 Restructuring Plan [Member] | Severance Costs [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance			1,420
Severance/other expense			2,534
Cash payments			(3,196)
Severance/restructuring and other accruals, Ending balance			758	1,420
2019 Restructuring Plan [Member] | Other Accruals [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance	[1]		$ 270
Severance/restructuring and other accruals, Ending balance	[1]			270
2018 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance				1,690	1,640
Severance/other expense					6,821
Cash payments					(6,771)
Severance/restructuring and other accruals, Ending balance					1,690
2018 Restructuring Plan [Member] | Severance Costs [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance				1,420	341
Severance/other expense					6,821
Cash payments					(5,742)
Severance/restructuring and other accruals, Ending balance					1,420
2018 Restructuring Plan [Member] | Other Accruals [Member]
Restructuring Cost and Reserve [Line Items]
Severance/restructuring and other accruals, Beginning balance				$ 270	1,299
Cash payments					(1,029)
Severance/restructuring and other accruals, Ending balance					$ 270
[1]	In connection with the adoption of the new leasing standard on January 1, 2019, the restructuring liabilities related to office space consolidation were reclassed on the balance sheet as a reduction of operating lease assets.

Income Taxes - Components of Lo

Income Taxes - Components of Loss Before Taxes by Jurisdiction (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Components Of Income Loss Before Income Taxes [Line Items]
Loss before taxes	$ (492,242)	$ (209,632)	$ (131,860)
U.S. [Member]
Schedule Of Components Of Income Loss Before Income Taxes [Line Items]
Loss before taxes	(494,456)	(213,541)	(134,884)
Foreign [Member]
Schedule Of Components Of Income Loss Before Income Taxes [Line Items]
Loss before taxes	$ 2,214	$ 3,909	$ 3,024

Income Taxes - Total Income Tax

Income Taxes - Total Income Tax by Jurisdiction (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income tax expense (benefit)
Income tax expense (benefit)	$ (12,404)	$ 4,201	$ 5,597
U.S. [Member]
Income tax expense (benefit)
Income tax expense (benefit)	(12,691)	4,273	3,701
Foreign [Member]
Income tax expense (benefit)
Income tax expense (benefit)	$ 287	$ (72)	$ 1,896

Income Taxes - Components of (B

Income Taxes - Components of (Benefit) Expense for Income Taxes Attributable to Loss from Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current
Foreign	$ 182	$ (730)	$ 1,562
U.S.—Federal		0	(63)
U.S.—State and other	1,769	396	(1,042)
Total current	1,951	(334)	457
Deferred
Foreign	105	658	334
U.S.—Federal	(5,505)	1,908	2,329
U.S.—State and other	(8,955)	1,969	2,477
Total deferred	(14,355)	4,535	5,140
Income tax (benefit) expense	$ (12,404)	$ 4,201	$ 5,597

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Tax Rate Computed at Statutory Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%	21.00%
Permanent items	(0.90%)	(3.60%)	(2.60%)
Foreign rate differential			(0.10%)
State and local taxes	2.00%	(7.90%)	6.80%
Cancellation of debt income		(1.30%)
Increase in valuation allowance	(15.50%)	(10.00%)	(26.60%)
Tax credits	(0.20%)	(0.20%)	(2.70%)
Goodwill impairment	(3.90%)
Effective tax rate	2.50%	(2.00%)	(4.20%)

Income Taxes - Components of Ne

Income Taxes - Components of Net Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Tax assets related to
Net operating loss and other carryforwards		$ 326,504	$ 272,378
Returns reserve/inventory expense		39,095	41,824
Pension benefits		6,879	6,624
Postretirement benefits		4,480	4,475
Deferred interest	[1]	226,227	259,375
Deferred revenue		141,775	113,029
Stock-based compensation		2,806	3,298
Deferred compensation		6,525	6,152
Research and development		12,435	10,302
Operating lease liabilities		33,963	35,890
Other, net		8,263	6,769
Valuation allowance		(662,569)	(583,505)
Deferred assets		146,383	176,611
Tax liabilities related to
Indefinite-lived intangible assets		(53,400)	(89,879)
Definite-lived intangible assets		(21,578)	(25,503)
Depreciation and amortization expense		(45,279)	(48,984)
Operating lease assets		(30,245)	(32,887)
Other, net		(9,877)	(7,709)
Deferred liabilities		(160,379)	(204,962)
Net deferred tax liabilities		$ (13,996)	$ (28,351)
[1]	The deferred interest tax asset represents disallowed interest deductions under Section 163(j) (Limitation on Deduction for interest on Certain Indebtedness) of the Internal Revenue Code of 1986, as amended (“IRC”) for the current and prior years. At December 31, 2020 and 2019, we had gross deferred interest deductions totaling $900.2 million and $984.5 million, respectively. The disallowed interest is able to be carried forward indefinitely and utilized in future years pursuant to IRC Section 163(j). A full valuation allowance has been provided against deferred tax assets, excluding $2.4 million of foreign deferred tax assets which are expected to be realized, net of deferred tax liabilities resulting from indefinite-lived intangibles.

Income Taxes - Components of _2

Income Taxes - Components of Net Deferred Tax Assets and Liabilities (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Gross deferred interest deductions	$ 900.2	$ 984.5
Foreign deferred tax assets	$ 2.4

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets and Liabilities Reflected on Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Non-current deferred tax assets	$ 2,415	$ 2,520
Non-current deferred tax liabilities	(16,411)	(30,871)
Net deferred tax liabilities	$ (13,996)	$ (28,351)

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of Gross Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Beginning balance	$ 15,680	$ 15,680	$ 15,680
Ending balance	$ 15,680	$ 15,680	$ 15,680

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Operating loss carry forwards reduced by reserve of uncertain tax positions	$ 123,600
Valuation allowance	662,569	$ 583,505
Increase (decrease) in valuation allowance	79,100
Continuing operations	76,700
Other comprehensive income	$ 2,400
Canada [Member]
Income Taxes [Line Items]
Loss carryforwards, description	expire between 2033 and 2037
Research and Development Credit Carryforwards [Member]
Income Taxes [Line Items]
Loss carryforwards	$ 4,200
Loss carryforwards, description	expire between 2021 and 2036
Alternative Minimum Tax Credit Carryforward [Member] | Puerto Rico [Member]
Income Taxes [Line Items]
Loss carryforwards	$ 2,800
Federal Tax [Member]
Income Taxes [Line Items]
Loss carryforwards	$ 1,058,800
Loss carryforwards, description	will expire between 2034 and 2037
Federal Tax [Member] | Expiry Between 2034 And 2037 [Member]
Income Taxes [Line Items]
Loss carryforwards	$ 612,500
Federal Tax [Member] | Post Tax Reform
Income Taxes [Line Items]
Loss carryforwards	$ 446,300
Loss carryforward, limitations on use by percentage of taxable income	80.00%
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Loss carryforwards	$ 1,419,500
Loss carryforwards, description	expire between 2021 and 2040
State and Local Jurisdiction [Member] | Canada [Member]
Income Taxes [Line Items]
Operating loss Carry forwards	$ 700
Foreign [Member]
Income Taxes [Line Items]
Loss carryforwards	7,300
Foreign [Member] | Ireland [Member]
Income Taxes [Line Items]
Operating loss Carry forwards	$ 142,600

Retirement and Postretirement_3

Retirement and Postretirement Benefit Plans - Summary of Accumulated Benefit Obligations ("ABO"), Change in Projected Benefit Obligation ("PBO"), and Funded Status of our Plans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Change in PBO
APBO at beginning of period	$ 16,684	$ 15,812
Interest cost on PBO	426	582
Actuarial loss (gain)	2,857	1,878
Benefits paid	(2,097)	(1,712)
APBO at end of period	18,121	16,684	$ 15,812
Change in plan assets
Fair market value at beginning of period	145,716
Company contribution	1,913	1,646
Benefits paid	(2,097)	(1,712)
Fair market value at end of period	153,754	145,716
Unfunded status	(18,121)	(16,684)
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
ABO at end of period	179,408	169,364
Change in PBO
APBO at beginning of period	169,364	162,096
Interest cost on PBO	4,388	6,045	5,300
Plan settlements	(4,990)
Actuarial loss (gain)	18,447	12,507
Benefits paid	(7,801)	(11,284)
APBO at end of period	179,408	169,364	162,096
Change in plan assets
Fair market value at beginning of period	145,716	132,776
Actual return	16,060	22,955
Company contribution	4,769	1,269
Plan settlements	(4,990)
Benefits paid	(7,801)	(11,284)
Fair market value at end of period	153,754	145,716	$ 132,776
Unfunded status	$ (25,654)	$ (23,648)

Retirement and Postretirement_4

Retirement and Postretirement Benefit Plans - Amounts Recognized in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Current liabilities	$ (1,593)
Noncurrent liabilities	(24,061)	$ (23,648)
Net amount recognized	$ (25,654)	$ (23,648)

Retirement and Postretirement_5

Retirement and Postretirement Benefit Plans - Additional Year-End Information for Pension Plans with ABO in Excess of Plan Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets	$ 153,754	$ 145,716
Projected Benefit Obligation [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
PBO	179,408	169,364
Accumulated Benefit Obligation [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
ABO	$ 179,408	$ 169,364

Retirement and Postretirement_6

Retirement and Postretirement Benefit Plans - Weighted Average Assumptions used to Determine Benefit Obligations (Detail)	Dec. 31, 2020	Dec. 31, 2019
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.20%	3.10%

Retirement and Postretirement_7

Retirement and Postretirement Benefit Plans - Net Periodic Benefit Cost Components (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost on APBO	$ 426	$ 582
Amortization of net loss	2,400	900	$ 900
Service cost	67	58
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost on APBO	4,388	6,045	5,300
Expected return on plan assets	(7,419)	(7,659)	(7,985)
Amortization of net loss	2,325	1,028	1,420
Settlement loss recognized	1,100
Net pension (income) expense recognized for the period	394	(586)	(1,265)
Other Post Retirement Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost on APBO	426	582	672
Amortization of net loss	(7)	(164)
Service cost	67	58	128
Amortization of unrecognized prior service cost	42	42	(690)
Net periodic postretirement benefit expense	$ 528	$ 518	$ 110

Retirement and Postretirement_8

Retirement and Postretirement Benefit Plans - Significant Actuarial Assumptions used to Determine Net Periodic Pension Cost (Detail) - Pension Plans [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	3.10%	4.20%	3.60%
Expected long-term rate of return on assets	5.50%	5.50%	5.50%

Retirement and Postretirement_9

Retirement and Postretirement Benefit Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Compensation And Retirement Disclosure [Line Items]
Defined benefit plan qualifying age	55 years
Defined benefit plan service period	5 years
Defined benefit plan contributions by plan participants, percentage	50.00%
Contribution expense	$ 6,800,000	$ 7,400,000	$ 7,600,000
Discretionary contributions	$ 0	$ 0	$ 0
Maximum [Member]
Compensation And Retirement Disclosure [Line Items]
Defined benefit plan contributions by employer, percentage	3.00%
Pension Plans [Member]
Compensation And Retirement Disclosure [Line Items]
Long-term rate of return	5.50%	5.50%	5.50%
Defined benefit plan expected contributions	$ 3,300,000
Pension Plans [Member] | Equity Securities [Member]
Compensation And Retirement Disclosure [Line Items]
Current targeted asset allocation	34.00%
Pension Plans [Member] | Fixed Income Securities [Member]
Compensation And Retirement Disclosure [Line Items]
Current targeted asset allocation	56.00%
Pension Plans [Member] | Real-estate Investments Trust Managers [Member]
Compensation And Retirement Disclosure [Line Items]
Current targeted asset allocation	5.00%
Pension Plans [Member] | Hedge Fund [Member]
Compensation And Retirement Disclosure [Line Items]
Current targeted asset allocation	5.00%
Other Post Retirement Plans [Member]
Compensation And Retirement Disclosure [Line Items]
Defined benefit plan expected contributions	$ 1,600,000

Retirement and Postretiremen_10

Retirement and Postretirement Benefit Plans - Summary of Assets Percentage Invested by Class (Detail)	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of assets invested in each asset class	100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of assets invested in each asset class	33.50%	32.60%
Fixed Income Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of assets invested in each asset class	52.70%	54.50%
Real Estate [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of assets invested in each asset class	7.00%	8.00%
Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of assets invested in each asset class	6.80%	4.90%

Retirement and Postretiremen_11

Retirement and Postretirement Benefit Plans - Summary of Fair Value of Pension Plan Assets by Asset Category (Detail) - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		$ 153,754	$ 145,716
Cash and Cash Equivalents [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		1,914	1,413
U.S. Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		27,765	28,993
Non-U.S. Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		15,544	12,474
Emerging Markets Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		8,259	5,537
Government Bonds [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		28,855	20,316
Corporate Bonds [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		46,228	37,925
Mortgage Backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		9	7,943
Asset-backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		810	3,255
Commercial Mortgage-Backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		604	1,930
International Fixed Income [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		4,485	5,741
Real Estate [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		10,689	11,609
Hedge Fund [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		8,228	7,043
Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset		364	1,537
Not Subject to Leveling [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	153,754	145,716
Not Subject to Leveling [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	1,914	1,413
Not Subject to Leveling [Member] | U.S. Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	27,765	28,993
Not Subject to Leveling [Member] | Non-U.S. Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	15,544	12,474
Not Subject to Leveling [Member] | Emerging Markets Equity [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	8,259	5,537
Not Subject to Leveling [Member] | Government Bonds [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	28,855	20,316
Not Subject to Leveling [Member] | Corporate Bonds [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	46,228	37,925
Not Subject to Leveling [Member] | Mortgage Backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	9	7,943
Not Subject to Leveling [Member] | Asset-backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	810	3,255
Not Subject to Leveling [Member] | Commercial Mortgage-Backed Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	604	1,930
Not Subject to Leveling [Member] | International Fixed Income [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	4,485	5,741
Not Subject to Leveling [Member] | Real Estate [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	10,689	11,609
Not Subject to Leveling [Member] | Hedge Fund [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	8,228	7,043
Not Subject to Leveling [Member] | Other [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined benefit plan asset	[1]	$ 364	$ 1,537
[1]	Investments that are valued using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy

Retirement and Postretiremen_12

Retirement and Postretirement Benefit Plans - Estimated Future Benefit Payments (Detail) - Pension Plans [Member] $ in Thousands	Dec. 31, 2020USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2021	$ 14,030
2022	12,817
2023	12,581
2024	12,789
2025	13,356
2026–2030	$ 61,944

Retirement and Postretiremen_13

Retirement and Postretirement Benefit Plans - Summary of Accumulated Postretirement Benefit Obligation Changes in Plan Assets and Funded Status of Plan (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans And Other Postretirement Benefit Plans Disclosures [Abstract]
APBO at beginning of period	$ 16,684	$ 15,812
Service cost (benefits earned during the period)	67	58
Interest cost on APBO	426	582
Employee contributions	184	66
Actuarial loss (gain)	2,857	1,878
Benefits paid	(2,097)	(1,712)
APBO at end of period	18,121	16,684
Change in plan assets
Fair market value at beginning of period	145,716
Company contributions	1,913	1,646
Employee contributions	184	66
Benefits paid	(2,097)	(1,712)
Fair market value at end of period	153,754	145,716
Unfunded status	$ (18,121)	$ (16,684)

Retirement and Postretiremen_14

Retirement and Postretirement Benefit Plans - Summary of Accrued Postretirement Benefits (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans And Other Postretirement Benefit Plans Disclosures [Abstract]
Current liabilities	$ (1,555)	$ (1,571)
Noncurrent liabilities	(16,566)	(15,113)
Net amount recognized	$ (18,121)	$ (16,684)

Retirement and Postretiremen_15

Retirement and Postretirement Benefit Plans - Amounts Not Yet Reflected in Net Periodic Benefit Cost and Recognized in Accumulated Other Comprehensive (Loss) Income (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated other comprehensive (loss) income	$ (48,966)	$ (39,757)	$ (41,557)
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated other comprehensive (loss) income	(44,219)	(35,010)
Net actuarial loss	(44,219)	(35,010)
Postretirement Benefit Costs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net (loss) gain	(1,050)	1,771
Prior service cost	(384)	(426)
Accumulated other comprehensive (loss) income	$ (1,434)	$ 1,345

Retirement and Postretiremen_16

Retirement and Postretirement Benefit Plans - Weighted Average Actuarial Assumptions Used to Determine APBO (Detail) - Accumulated Postretirement Benefit Obligation [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Defined Benefit Plans Actuarial Assumptions Used In Calculating Net Benefit Obligations [Line Items]
Discount rate	2.20%	3.10%
Health care cost trend rate assumed for next year	5.50%	5.80%
Rate to which the cost trend rate is assumed to decline (ultimate trend rate)	4.50%	4.50%
Year that the rate reaches the ultimate trend rate	2038	2038

Retirement and Postretiremen_17

Retirement and Postretirement Benefit Plans - Significant Actuarial Assumptions used to Determine Post Retirement Benefit Cost (Detail) - Other Post Retirement Plans [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	3.10%	4.20%	3.60%
Health care cost trend rate assumed for next year	5.80%	6.10%	6.30%
Rate to which the cost trend rate is assumed to decline (ultimate trend rate)	4.50%	4.50%	4.50%
Year that the rate reaches the ultimate trend rate	2038	2038	2038

Retirement and Postretiremen_18

Retirement and Postretirement Benefit Plans - One Percentage Point Changes in Assumed Health Care Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans And Other Postretirement Benefit Plans Disclosures [Abstract]
Effect on total of service and interest cost components	$ 2	$ 8
Effect on postretirement benefit obligation	87	85
Effect on total of service and interest cost components	(2)	(7)
Effect on postretirement benefit obligation	$ (77)	$ (76)

Retirement and Postretiremen_19

Retirement and Postretirement Benefit Plans - Summary of Change in Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Net loss arising during the period	$ (12,621)
Amortization of prior service credit	42
Amortization of net gain (loss)	3,370
Total accumulated other comprehensive loss recognized during the period	(9,209)	$ 1,800	$ (2,056)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss arising during the period	(9,807)
Amortization of net gain (loss)	3,377
Total accumulated other comprehensive loss recognized during the period	(6,430)
Other Post Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss arising during the period	(2,814)
Amortization of prior service credit	42
Amortization of net gain (loss)	(7)
Total accumulated other comprehensive loss recognized during the period	$ (2,779)

Retirement and Postretiremen_20

Retirement and Postretirement Benefit Plans - Summary of Estimated Amounts Amortized from Accumulated Other Comprehensive Income (Loss) Over Next Fiscal Year (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss)	$ (3,389)
Defined benefit plan, amount to be amortized from accumulated other comprehensive income (loss) next fiscal year, total	(3,389)
Other Post Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost)	(42)
Defined benefit plan, amount to be amortized from accumulated other comprehensive income (loss) next fiscal year, total	$ (42)

Retirement and Postretiremen_21

Retirement and Postretirement Benefit Plans - Expected Future Benefit Payments (Detail) - Other Post Retirement Plans [Member] $ in Thousands	Dec. 31, 2020USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2021	$ 1,555
2022	1,488
2023	1,437
2024	1,389
2025	1,320
2026–2030	$ 5,686

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)		May 19, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 19, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 11,573,000	$ 13,968,000	$ 13,248,000
Minimum price of options			$ 5.25
Maximum price of options			$ 22.80
Weighted average remaining contractual life			3 years 3 months 18 days
Weighted average remaining contractual life for options vested and expected to vest			3 years 3 months 18 days
Weighted average remaining contractual life for options exercisable			3 years 1 month 6 days
Intrinsic value of options outstanding			$ 0	100,000
Intrinsic value of options vested and expected to vest			0	100,000
Intrinsic value of options exercisable			0	0
Unrecognized compensation expense			$ 600,000
Unrecognized compensation expense, recognition period			9 months 18 days
Weighted average grant date fair value, options granted					$ 1.82
Fair value assumptions, expected term	[1]				4 years 9 months
Fair value assumptions, risk-free rate	[2]				2.84%
Expense associated with ESPP			$ 400,000	$ 400,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, recognition period			1 year 6 months
Performance measurement period for award of restricted stock units			3 years
Fair value assumptions, expected term			3 years
Fair value of restricted stock units			$ 2,900,000		$ 3,100,000
Fair value assumptions, risk-free rate			0.40%	2.51%
Period to recognize expense on straight-line basis			3 years
Unrecognized compensation expense			$ 11,900,000
Restricted Stock Units [Member] | Grant Date One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value assumptions, stock price			$ 4.21	$ 7.75
Restricted Stock Units [Member] | Grant Date Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value assumptions, stock price				6.71
Restricted Stock Units [Member] | Grant Date Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value assumptions, stock price				$ 6.53
2015 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future issuance			6,996,290			4,000,000
Number of shares authorized for issuance						6,615,476
Share based compensation, expiration period			7 years
2015 Omnibus Incentive Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting terms			1 year
2015 Omnibus Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting terms			4 years
2015 Omnibus Incentive Plan [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in authorization of number of shares available for grant		3,630,000
2012 Management Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future issuance						2,615,476
Common stock additional capital shares reserved for future issuance						10,604,071
Employees Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant						1,300,000
Employee stock purchase plan,description			At the beginning of each six-month offering period under the ESPP each participant is deemed to have been granted an option to purchase shares of our common stock equal to the amount of their payroll deductions during the period, but in any event not more than five percent of the employee’s eligible compensation, subject to certain limitations. Such options may be exercised only to the extent of accumulated payroll deductions at the end of the offering period, at a purchase price per share equal to 85% of the fair market value of our common stock at the beginning or end of each offering period, whichever is less.
Percentage of fair value expressed as purchase price of common stock			85.00%
Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 11,600,000	$ 14,000,000	$ 13,300,000
[1]	The expected term is the number of years that we estimate that options will be outstanding prior to exercise. During 2018, we have used the simplified method for estimating the expected term as we do not have sufficient stock option exercise experience to support a reasonable estimate of the expected term. The simplified method represents the best estimate of the expected term.
[2]	The risk-free interest rate is based on the U.S. Treasury yield for a period commensurate with the expected life of the option.

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Option Activity (Detail)	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Number of Shares
Outstanding at beginning of period | shares	2,765,826
Forfeited | shares	(868,614)
Outstanding at end of period | shares	1,897,212
Vested and expected to vest at end of the year | shares	1,883,100
Exercisable at end of year | shares	1,521,524
Weighted Average Exercise Price
Outstanding at beginning of period | $ / shares	$ 13.10
Forfeited | $ / shares	13.40
Outstanding at end of period | $ / shares	12.95
Vested and expected to vest at end of the year | $ / shares	12.97
Exercisable at end of year | $ / shares	$ 13.65

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Each Option Granted was Estimated on Grant Date using Black-Scholes Valuation Model (Detail)	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Expected term (years)	4 years 9 months	[1]
Expected dividend yield	0.00%
Expected volatility	35.30%	[2]
Risk-free interest rate	2.84%	[3]
[1]	The expected term is the number of years that we estimate that options will be outstanding prior to exercise. During 2018, we have used the simplified method for estimating the expected term as we do not have sufficient stock option exercise experience to support a reasonable estimate of the expected term. The simplified method represents the best estimate of the expected term.
[2]	During 2018, we estimated volatility for options granted based on our historical volatility.
[3]	The risk-free interest rate is based on the U.S. Treasury yield for a period commensurate with the expected life of the option.

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Restricted Stock Activity for Grants to Certain Executive Employees and Independent Members of Board of Directors (Detail) - Restricted Stock Units [Member]	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Number of Units
Outstanding at beginning of the year | shares	3,846,608
Granted | shares	3,716,974
Vested | shares	(1,149,957)
Forfeited | shares	(723,816)
Outstanding at end of period | shares	5,689,809
Weighted-Average Grant Date Fair Value per Share
Outstanding at beginning of the year | $ / shares	$ 8.03
Granted | $ / shares	3.94
Vested | $ / shares	8.50
Forfeited | $ / shares	7.41
Outstanding at end of period | $ / shares	$ 5.34

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Shares Issued or to be Issued in Connection with the ESPP (Detail) - Employees Stock Purchase Plan [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued or to be issued	516,563	212,476
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of purchase prices	$ 1.54	$ 4.73
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of purchase prices	$ 1.56	$ 4.90

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets
Financial assets	$ 262,601	$ 276,654
Financial liabilities
Financial liabilities		1,113
Foreign Exchange Derivatives [Member]
Financial liabilities
Financial liabilities		127
Interest Rate Derivatives [Member]
Financial liabilities
Financial liabilities		986
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Financial assets	262,135	276,654
Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Financial assets	466
Financial liabilities
Financial liabilities		1,113
Significant Other Observable Inputs (Level 2) [Member] | Foreign Exchange Derivatives [Member]
Financial liabilities
Financial liabilities		127
Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Derivatives [Member]
Financial liabilities
Financial liabilities		986
Money Market Funds [Member]
Financial assets
Financial assets	262,135	276,654
Money Market Funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets
Financial assets	262,135	$ 276,654
Foreign Exchange Derivatives [Member]
Financial assets
Financial assets	466
Foreign Exchange Derivatives [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets
Financial assets	$ 466

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets			$ 262,601,000	$ 276,654,000
Non-financial liabilities fair value			0	0
Impairment charge for goodwill	$ 0	$ 262,000,000	279,000,000	0	$ 0
Impairment of intangible assets			0	0	0
Non-marketable investments			4,400,000	2,300,000
Gains from non-marketable investments			2,091,000
Other Intangible Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of intangible assets			0	0	$ 0
Foreign Exchange Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivative instruments			14,900,000	15,200,000
Interest Rate Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivative instruments			0
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of counterparty default exposure			1,000,000	1,000,000
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets			262,135,000	276,654,000
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets			262,135,000	276,654,000
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets			262,135,000	276,654,000
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Bank Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets			$ 19,100,000	$ 19,700,000

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Non-financial Assets Measured at Fair Value on Nonrecurring Basis (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-financial assets	$ 437,977
Total Impairment	279,000
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-financial assets	437,977
Goodwill [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-financial assets	437,977
Total Impairment	279,000
Goodwill [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non-financial assets	$ 437,977

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of Carrying Amounts and Estimated Fair Market Values of Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments [Line Items]
Debt, carrying value	$ 643,692	$ 657,187
Term Loan [Member]
Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments [Line Items]
Debt, carrying value	346,091	361,294
Debt, estimated fair value	331,382	360,391
$306,000 Senior Secured Notes [Member]
Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments [Line Items]
Debt, carrying value	297,601	295,893
Debt, estimated fair value	$ 304,297	$ 301,441

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Sep. 30, 2019	Apr. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Guarantee expiration period			2022
Guarantee future payments			$ 10,100,000
Performance related surety bonds for which the Company is contingently liable			1,400,000	$ 2,500,000
Aggregate letter of credit			18,800,000	23,700,000
Letter of credit backed by performance related surety bonds			1,100,000	700,000
Indemnification liabilities			$ 0	$ 0
Minimum [Member]
Loss Contingencies [Line Items]
Liable for portion of damages	$ 1,400,000
Requirement of warranty insurance for damages limit amount	2,800,000
Unasserted Claim [Member]
Loss Contingencies [Line Items]
Unasserted claim, payments in the amount		$ 33,000,000
Unasserted Claim [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Unasserted claim, payments in the amount	$ 1,400,000

Stockholders' Equity - Accumula

Stockholders' Equity - Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Net change in pension and benefit plan liabilities	$ (48,966)	$ (39,757)	$ (41,557)
Foreign currency translation adjustments	(6,650)	(6,420)	(5,909)
Unrealized loss on short-term investments	(90)	(90)	(99)
Net change in unrealized loss on derivative instruments	(18)	(1,005)	2,381
Accumulated other comprehensive loss	$ (55,724)	$ (47,272)	$ (45,184)

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Amortization of defined benefit pension and postretirement benefit plans	$ (2.4)	$ (0.9)	$ (0.9)

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Nov. 22, 2019
Senior Secured Notes [Member]
Related Party Transaction [Line Items]
Term loan, face amount			$ 306,000
Debt instrument, interest rate, stated percentage			9.00%
Senior Secured Notes [Member] | Anchorage [Member]
Related Party Transaction [Line Items]
Term loan, face amount			$ 20,000
Debt instrument, interest rate, stated percentage			9.00%
Term Loan [Member] | Term Loan Due November 22, 2024 [Member]
Related Party Transaction [Line Items]
Term loan, face amount	$ 380,000	$ 380,000	$ 380,000
Term Loan [Member] | Anchorage [Member] | Term Loan Due November 22, 2024 [Member]
Related Party Transaction [Line Items]
Term loan, face amount			$ 15,000

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Basic and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator
Loss from continuing operations									$ (479,838)	$ (213,833)	$ (137,457)
Earnings from discontinued operations, net of tax											12,833
Gain on sale of discontinued operations, net of tax											30,469
Income from discontinued operations, net of tax											43,302
Net loss	$ (83,145)	$ (12,552)	$ (38,168)	$ (345,973)	$ (125,118)	$ 69,260	$ (40,613)	$ (117,362)	$ (479,838)	$ (213,833)	$ (94,155)
Denominator
Weighted average shares outstanding Basic and diluted									125,455,487	124,152,984	123,444,943
Net loss per share attributable to common stockholders
Continuing operations									$ (3.82)	$ (1.72)	$ (1.11)
Discontinued operations											0.35
Net loss									$ (3.82)	$ (1.72)	$ (0.76)

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Anti-Dilutive Securities Excluded from Computation of Diluted EPS (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted EPS	1,897,212	2,765,826	3,406,171
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of diluted EPS	4,133,531	3,342,923	2,793,680

Segment Reporting - Additional

Segment Reporting - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020Segment
Segment Reporting [Abstract]
Number of reportable segments	2

Segment Reporting - Consolidate

Segment Reporting - Consolidated Net Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 203,561	$ 386,590	$ 251,216	$ 189,925	$ 241,475	$ 565,668	$ 388,896	$ 194,635	$ 1,031,292	$ 1,390,674	$ 1,322,417
Segment Adjusted EBITDA									172,489	211,815	232,546
Education [Member]
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA									145,862	196,907	210,604
HMH Books & Media [Member]
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA									26,627	14,908	21,942
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									1,031,292	1,390,674	1,322,417
Operating Segments [Member] | Education [Member]
Segment Reporting Information [Line Items]
Net sales									839,553	1,210,646	1,122,689
Segment Adjusted EBITDA									145,862	196,907	210,604
Operating Segments [Member] | HMH Books & Media [Member]
Segment Reporting Information [Line Items]
Net sales									191,739	180,028	199,728
Segment Adjusted EBITDA									26,627	14,908	21,942
Corporate/Other [Member]
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA									$ (40,649)	$ (46,077)	$ (40,418)

Segment Reporting - Summary of

Segment Reporting - Summary of Net Sales (Detail) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net sales		$ 203,561	$ 386,590	$ 251,216	$ 189,925	$ 241,475	$ 565,668	$ 388,896	$ 194,635	$ 1,031,292	$ 1,390,674	$ 1,322,417
Operating Segments [Member]
Net sales										1,031,292	1,390,674	1,322,417
Operating Segments [Member] | Education [Member]
Net sales										839,553	1,210,646	1,122,689
Operating Segments [Member] | HMH Books & Media [Member]
Net sales										191,739	180,028	199,728
Core Solutions [Member] | Operating Segments [Member]
Net sales	[1]									459,350	578,675	538,166
Core Solutions [Member] | Operating Segments [Member] | Education [Member]
Net sales	[1]									459,350	578,675	538,166
Extension Businesses [Member] | Operating Segments [Member]
Net sales	[2]									380,203	631,971	584,523
Extension Businesses [Member] | Operating Segments [Member] | Education [Member]
Net sales	[2]									380,203	631,971	584,523
Books & Media [Member] | Operating Segments [Member]
Net sales										191,739	180,028	199,728
Books & Media [Member] | Operating Segments [Member] | HMH Books & Media [Member]
Net sales										$ 191,739	$ 180,028	$ 199,728
[1]	Comprehensive solutions primarily for reading, literature, math, science and social studies programs.
[2]	Primarily consists of our Heinemann brand, intervention, supplemental and professional services.

Segment Reporting - Consolida_2

Segment Reporting - Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total Segment Adjusted EBITDA	$ 172,489	$ 211,815	$ 232,546
Interest expense	(65,959)	(48,778)	(45,680)
Interest income	899	3,157	2,550
Depreciation expense	(50,715)	(61,475)	(75,116)
Amortization expense—film asset	(13,953)	(9,835)	(6,057)
Amortization expense	(171,821)	(201,382)	(170,903)
Non-cash charges—stock compensation	(11,573)	(13,968)	(13,248)
Non-cash charges—loss on derivative instruments	672	(899)	(1,374)
Non-cash charges—asset impairment charges	(279,000)
Inventory obsolescence related to strategic transformation plan		(9,758)
Fees, expenses or charges for equity offerings, debt or acquisitions/dispositions	(1,080)	(6,327)	(2,883)
Restructuring/severance and other charges	(33,643)	(21,742)	(11,478)
Gain on investments	2,091
Gain on sale of assets			201
Loss on extinguishment of debt		(4,363)
Loss from continuing operations before taxes	(492,242)	(209,632)	(131,860)
(Provision) benefit for income taxes	12,404	(4,201)	(5,597)
Loss from continuing operations	(479,838)	(213,833)	(137,457)
Education [Member]
Segment Reporting Information [Line Items]
Total Segment Adjusted EBITDA	145,862	196,907	210,604
HMH Books & Media [Member]
Segment Reporting Information [Line Items]
Total Segment Adjusted EBITDA	26,627	14,908	21,942
Corporate/other [Member]
Segment Reporting Information [Line Items]
Total Segment Adjusted EBITDA	$ (40,649)	$ (46,077)	$ (40,418)

Segment Reporting - Segment Inf

Segment Reporting - Segment Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total Assets	$ 2,021,126	$ 2,513,172
Education [Member]
Segment Reporting Information [Line Items]
Total Assets	1,520,504	1,971,553
HMH Books & Media [Member]
Segment Reporting Information [Line Items]
Total Assets	175,710	186,318
Corporate/other [Member]
Segment Reporting Information [Line Items]
Total Assets	$ 324,912	$ 355,301

Segment Reporting - Schedule of

Segment Reporting - Schedule of Long-Lived Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting [Abstract]
Long-lived assets—International	$ 228	$ 113

Segment Reporting - Schedule _2

Segment Reporting - Schedule of Net Sales by Geographic Region (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 203,561	$ 386,590	$ 251,216	$ 189,925	$ 241,475	$ 565,668	$ 388,896	$ 194,635	$ 1,031,292	$ 1,390,674	$ 1,322,417
U.S. [Member]
Segment Reporting Information [Line Items]
Net sales									997,178	1,327,833	1,249,568
International [Member]
Segment Reporting Information [Line Items]
Net sales									$ 34,114	$ 62,841	$ 72,849

Valuation and Qualifying Acco_3

Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 119,700
Balance at End of Year	96,700	$ 119,700
Allowance for Bad Debt [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	3,015	2,173	$ 2,508
Net Charges	1,589	1,909	128
Utilization of Allowances	(615)	(1,067)	(463)
Balance at End of Year	3,989	3,015	2,173
Reserve for Book Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	16,679	18,559	20,580
Net Charges	33,847	41,654	36,395
Utilization of Allowances	(35,952)	(43,534)	(38,416)
Balance at End of Year	14,574	16,679	18,559
Reserve for Royalty Advances [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	119,695	117,797	103,606
Net Charges	16,552	16,500	17,301
Utilization of Allowances	(39,592)	(14,602)	(3,110)
Balance at End of Year	96,655	119,695	117,797
Deferred Tax Valuation Allowance [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	583,505	562,392	571,653
Net Charges	81,475	23,707	(7,667)
Utilization of Allowances	(2,412)	(2,594)	(1,594)
Balance at End of Year	$ 662,568	$ 583,505	$ 562,392

Quarterly Results of Operatio_3

Quarterly Results of Operations (Unaudited) - Quarterly Results of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 203,561	$ 386,590	$ 251,216	$ 189,925	$ 241,475	$ 565,668	$ 388,896	$ 194,635	$ 1,031,292	$ 1,390,674	$ 1,322,417
Gross profit	65,986	167,415	90,389	63,450	59,065	273,481	156,055	57,893
Operating (loss) income	(68,973)	272	(22,212)	(338,176)	(108,947)	77,871	(30,253)	(101,835)	(429,089)	(163,164)	(90,525)
Net loss	$ (83,145)	$ (12,552)	$ (38,168)	$ (345,973)	$ (125,118)	$ 69,260	$ (40,613)	$ (117,362)	$ (479,838)	$ (213,833)	$ (94,155)
Basic:
Net (loss) income	$ (0.66)	$ (0.10)	$ (0.30)	$ (2.77)	$ (1.01)	$ 0.56	$ (0.33)	$ (0.95)
Diluted:
Net (loss) income	$ (0.66)	$ (0.10)	$ (0.30)	$ (2.77)	$ (1.01)	$ 0.55	$ (0.33)	$ (0.95)

Quarterly Results of Operatio_4

Quarterly Results of Operations (Unaudited) - Additional Information (Detail) - USD ($)	3 Months Ended			12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Results Of Operations [Line Items]
Prior period adjustment description				Management believes these adjustments are not material to the current period financial statements or any prior periods
Goodwill impairment		$ 0	$ 262,000,000	$ 279,000,000	$ 0	$ 0
Goodwill Impairment Charge [Member]
Quarterly Results Of Operations [Line Items]
Prior period correction amounts	$ 17,000,000
Income Tax Benefit [Member]
Quarterly Results Of Operations [Line Items]
Prior period correction amounts	$ 1,000,000