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Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Aug. 13, 2021 | Dec. 31, 2018
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Foreign earnings inclusion, Global Intangible Low-Taxed Income (GILTI) |  |  |  |  |  | $ 16.8 |  |
Repatriation of foreign earnings (GILTI ) |  |  | $ 2.0 |  | $ 0.2 | 3.5 |  |
Restructuring |  |  | 0.0 |  | 0.0 | 4.2 |  |
Valuation allowance |  |  | 17.6 |  | 335.5 | (89.1) |  |
Valuation allowance increase (decrease) due to change in judgment on the realizability of deferred tax assets |  |  |  |  |  | (45.1) |  |
Discrete tax effects related to valuation allowance |  |  | 11.6 |  |  |  |  |
Additional valuation allowance required |  |  | 5.2 |  |  |  |  |
Accumulated other comprehensive loss, net of tax |  | $ 1,201.7 | 991.7 |  | 1,223.6 | 1,201.7 |  | $ 1,133.8
Tax expense for the recognition of a stranded deferred tax balance arising from deferred tax valuation allowances that was associated with a cash flow hedge portfolio |  | 6.0 |  |  |  |  |  |
Impairment of goodwill |  |  | 0.0 |  | 287.0 | 0.0 |  |
Goodwill |  |  | 2.6 |  | 50.4 | 0.0 |  |
Deferred taxes for foreign withholding taxes |  |  | 7.8 |  |  |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax |  |  | (111.3) |  | (58.3) | (69.0) |  |
Goodwill |  |  | (227.9) |  | (240.7) |  |  |
Income tax provision (benefit) |  |  | 26.8 |  | 77.7 | (28.5) |  |
Recognition of stranded deferred tax balance |  |  | 3.9 |  | 0.0 | 0.0 |  |
Settlement gain |  |  | (21.9) |  | 0.0 | 0.0 |  |
Tax expense for the recognition of a stranded deferred tax balance arising from deferred tax valuation allowances that was associated with certain postretirement medical benefits due to plan termination |  |  | 6.4 |  |  |  |  |
Collective-Bargaining Arrangement, Other |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Income tax provision (benefit) |  |  | 15.5 |  |  |  |  |
Flowform Products |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  | $ (12.2) |
Accounting Standards Update 2020-06 |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Valuation allowance increase (decrease) due to change in judgment on the realizability of deferred tax assets |  |  | 12.3 |  |  |  |  |
Accumulated Deferred Tax Asset Valuation Allowance |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive loss, net of tax |  | 41.5 | (15.8) |  | 50.3 | 41.5 |  | 49.3
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | [1] |  | (66.1) |  | 8.8 | (7.8) |  |
Post- retirement benefit plans [Member] |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Accumulated other comprehensive loss, net of tax |  | $ 1,083.1 | 947.7 |  | 1,119.9 | 1,083.1 |  | $ 1,005.8
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | [2] |  | (53.9) |  | (62.5) | (64.3) |  |
Post- retirement benefit plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Income tax provision (benefit) | [3] |  | (11.9) |  | (19.7) | (20.3) |  |
Settlement gain |  |  | 21.9 | [4] | $ 0.0 | $ 0.0 |  |
State [Member] |  |  |  |  |  |  |  |
NOL and Tax Credit Carryforwards [Line Items] |  |  |  |  |  |  |  |
Valuation allowance increase (decrease) due to change in judgment on the realizability of deferred tax assets |  |  | $ 5.4 |  |  |  |  |
[1] | Represents the net change in deferred tax asset valuation allowances on changes in AOCI balances between the balance sheet dates. The 2021 income tax provision includes $6.4 million of tax expense for the recognition of a stranded deferred tax balance arising from deferred tax valuation allowances that was associated with certain postretirement medical benefits due to plan termination (see Notes 14 and 17). The 2019 income tax provision includes $6.0 million of tax expense for the recognition of a stranded deferred tax balance arising from deferred tax valuation allowances that was associated with a cash flow hedge portfolio that fully settled in the fourth quarter of 2019.
[2] | Amounts were included in net periodic benefit cost for pension and other postretirement benefit plans (see Note 14).
[3] | These amounts exclude the impact of any deferred tax asset valuation allowances, when applicable, including recognition of stranded balances (see Note 17 for further explanation).
[4] | Amounts are included in nonoperating retirement benefit expense (see Note 14).

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