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Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Operating Loss Carryforwards [Line Items] |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | $ 1.4 |
Deferred Tax Assets, Operating Loss Carryforwards, State and Local | 14.0 |
Deferred tax assets |  |
Net operating loss carryforwards | 15.4 | $ 16.5
Tax credit carryforwards | 27.9 | 40.8
Restructuring and impairment charges | 2.9 | 0.0
Pension and deferred compensation | 46.4 | 42.0
Other | 19.5 | 19.3
Valuation allowance | (18.7) | (20.1)
Total deferred tax assets | 93.4 | 98.5
Deferred tax liabilities: |  |
Accelerated depreciation | 30.3 | 35.0
Other | 6.1 | 5.4
Total deferred tax liabilities | 36.4 | 40.4
Net deferred tax asset | 57.0 | $ 58.1
State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Operating Loss Carryforwards | 254.8 |
Foreign Tax Authority [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 8.2 |
Operating Loss Carryforwards | 9.4 |
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration | 6.2 |
Year After 2016 [Domain] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Operating Loss Carryforwards | 249.5 |
Year 2019 [Member] | Foreign Tax Authority [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 3.2 |
Year 2020 [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 0.9 |
Year 2020 [Member] | Foreign Tax Authority [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 5.0 |
Year 2016 [Domain] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Operating Loss Carryforwards | 5.3 |
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 3.0 |
Research Tax Credit Carryforward [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 12.0 |
Research Tax Credit Carryforward [Member] | Year 2028 [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 0.6 |
Research Tax Credit Carryforward [Member] | Year 2029 [Domain] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 1.1 |
Research Tax Credit Carryforward [Member] | Year 2030 [Domain] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 1.0 |
Research Tax Credit Carryforward [Member] | Year 2031 [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 1.0 |
Research Tax Credit Carryforward [Member] | Year 2032 [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 1.4 |
Research Tax Credit Carryforward [Member] | Year 2033 [Member] [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 1.4 |
Research Tax Credit Carryforward [Member] | Year After 2033 [Domain] [Member] | Internal Revenue Service (IRS) [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 5.5 |
Research Tax Credit Carryforward [Member] | Year 2021 [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 0.2 |
Research Tax Credit Carryforward [Member] | Year 2022 [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 0.8 |
Research Tax Credit Carryforward [Member] | Year 2023 [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | 0.5 |
Research Tax Credit Carryforward [Member] | Year After 2023 [Member] | State and Local Jurisdiction [Member] |  |
Operating Loss Carryforwards [Line Items] |  |
Tax Credit Carryforward, Amount | $ 1.5 |

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