0000001 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY link:presentationLink link:calculationLink link:definitionLink 9952156 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952157 - Disclosure - Description of business and basis of presentation link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Revenues link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Accounts receivable, net link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Goodwill and intangible assets link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Integration and reorganization costs link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Debt link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Pensions and other postretirement benefit plans link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Fair value measurement link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Income taxes link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Supplemental equity and other information link:presentationLink link:calculationLink link:definitionLink 9952167 - Disclosure - Commitments, contingencies, and other matters link:presentationLink link:calculationLink link:definitionLink 9952168 - Disclosure - Segment reporting link:presentationLink link:calculationLink link:definitionLink 9952169 - Disclosure - Other supplemental information link:presentationLink link:calculationLink link:definitionLink 9955511 - Disclosure - Description of business and basis of presentation (Policies) link:presentationLink link:calculationLink link:definitionLink 9955512 - Disclosure - Revenues (Tables) link:presentationLink link:calculationLink link:definitionLink 9955513 - Disclosure - Accounts receivable, net (Tables) link:presentationLink link:calculationLink link:definitionLink 9955514 - Disclosure - Goodwill and intangible assets (Tables) link:presentationLink link:calculationLink link:definitionLink 9955515 - Disclosure - Integration and reorganization costs (Tables) link:presentationLink link:calculationLink link:definitionLink 9955516 - Disclosure - Debt (Tables) link:presentationLink link:calculationLink link:definitionLink 9955517 - Disclosure - Pensions and other postretirement benefit plans (Tables) link:presentationLink link:calculationLink link:definitionLink 9955518 - Disclosure - Income taxes (Tables) link:presentationLink link:calculationLink link:definitionLink 9955519 - Disclosure - Supplemental equity and other information (Tables) link:presentationLink link:calculationLink link:definitionLink 9955520 - Disclosure - Segment reporting (Tables) link:presentationLink link:calculationLink link:definitionLink 9955521 - Disclosure - Other supplemental information (Tables) link:presentationLink link:calculationLink link:definitionLink 9955522 - Disclosure - Description of business and basis of presentation (Details) link:presentationLink link:calculationLink link:definitionLink 9955523 - Disclosure - Revenues - Schedule of Disaggregation of Revenue (Details) link:presentationLink link:calculationLink link:definitionLink 9955524 - Disclosure - Revenues - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955524 - Disclosure - Revenues - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955525 - Disclosure - Revenues - Schedule of Deferred Revenue (Details) link:presentationLink link:calculationLink link:definitionLink 9955526 - Disclosure - Accounts receivable, net - Schedule of Allowance for Credit Losses (Details) link:presentationLink link:calculationLink link:definitionLink 9955527 - Disclosure - Accounts receivable, net - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955528 - Disclosure - Goodwill and intangible assets - Schedule of Goodwill and Intangible Assets (Details) link:presentationLink link:calculationLink link:definitionLink 9955529 - Disclosure - Goodwill and intangible assets - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955530 - Disclosure - Integration and reorganization costs - Schedule of Severance-Related Expenses (Details) link:presentationLink link:calculationLink link:definitionLink 9955531 - Disclosure - Integration and reorganization costs - Schedule of Restructuring Reserve (Details) link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Integration and reorganization costs - Schedule of Other Reorganization-Related Charges (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Debt - Schedule of Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Debt - Schedule of Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9955534 - Disclosure - Debt - 2029 Term Loan Facility (Details) link:presentationLink link:calculationLink link:definitionLink 9955535 - Disclosure - Debt - Senior Secured Convertible Notes due 2027, Senior Secured Convertible Notes due 2031, and the Convertible Notes Exchange (Details) link:presentationLink link:calculationLink link:definitionLink 9955536 - Disclosure - Pensions and other postretirement benefit plans - Schedule of Components of Net Periodic Pension and Postretirement Benefits (Details) link:presentationLink link:calculationLink link:definitionLink 9955537 - Disclosure - Pensions and other postretirement benefit plans - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955538 - Disclosure - Income taxes - Schedule of Pre-tax Net Income (Loss) and Income Tax (Details) link:presentationLink link:calculationLink link:definitionLink 9955539 - Disclosure - Income taxes - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955540 - Disclosure - Supplemental equity and other information - Schedule of Basic and Diluted Income Per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9955541 - Disclosure - Supplemental equity and other information - Schedule of Securities Excluded From Computation of Diluted Income Per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9955542 - Disclosure - Supplemental equity and other information - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955543 - Disclosure - Supplemental equity and other information - Schedule of Accumulated Other Comprehensive Loss, Net of Tax (Details) link:presentationLink link:calculationLink link:definitionLink 9955544 - Disclosure - Segment reporting - Schedule of Revenue Information (Details) link:presentationLink link:calculationLink link:definitionLink 9955545 - Disclosure - Segment reporting - Schedule of Reconciliation of Segment Adjusted EBITDA (Details) link:presentationLink link:calculationLink link:definitionLink 9955546 - Disclosure - Segment reporting - Schedule of Reconciliation of Segment Adjusted EBTIDA to Loss Before Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9955547 - Disclosure - Other supplemental information - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955548 - Disclosure - Other supplemental information - Schedule of Cash, Cash Equivalents and Restricted Cash (Details) link:presentationLink link:calculationLink link:definitionLink 9955549 - Disclosure - Other supplemental information - Schedule of Supplemental Cash Flow Information (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Other supplemental information - Schedule of Accounts Payable and Accrued Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink