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Postretirement and Other Benefits - Fair Value of Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
United States |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | $ 128.7 | $ 118.9
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 128.7 | 118.9
Fair value of plan assets at end of year | 113.1 | 128.7
United States | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.1 | 1.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.1 |
Fair value of plan assets at end of year | 1.0 | 1.1
United States | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 9.0 | 9.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 9.0 |
Fair value of plan assets at end of year | 5.7 | 9.0
United States | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 5.8 | 5.8
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 5.8 |
Fair value of plan assets at end of year | 3.3 | 5.8
United States | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 25.3 | 25.3
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 25.3 |
Fair value of plan assets at end of year | 15.5 | 25.3
United States | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 87.4 | 87.4
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 87.4 |
Fair value of plan assets at end of year | 87.6 | 87.4
United States | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.1 | 0.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.1 |
Fair value of plan assets at end of year | 0.0 | 0.1
United States | Fair Value Measured at Net Asset Value Per Share [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 71.2 | 71.2
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 71.2 |
Fair value of plan assets at end of year | 65.7 | 71.2
United States | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 9.0 | 9.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 9.0 |
Fair value of plan assets at end of year | 5.7 | 9.0
United States | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 5.8 | 5.8
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 5.8 |
Fair value of plan assets at end of year | 3.3 | 5.8
United States | Fair Value Measured at Net Asset Value Per Share [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 25.3 | 25.3
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 25.3 |
Fair value of plan assets at end of year | 15.5 | 25.3
United States | Fair Value Measured at Net Asset Value Per Share [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 31.1 | 31.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 31.1 |
Fair value of plan assets at end of year | 41.2 | 31.1
United States | Level 1 [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.1 | 1.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.1 |
Fair value of plan assets at end of year | 1.0 | 1.1
United States | Level 1 [Member] | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.1 | 1.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.1 |
Fair value of plan assets at end of year | 1.0 | 1.1
United States | Level 1 [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 1 [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 1 [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 1 [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 1 [Member] | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 2 [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 56.3 | 56.3
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 56.3 |
Fair value of plan assets at end of year | 46.4 | 56.3
United States | Level 2 [Member] | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 2 [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 2 [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 2 [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 2 [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 56.3 | 56.3
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 56.3 |
Fair value of plan assets at end of year | 46.4 | 56.3
United States | Level 2 [Member] | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.1 | 0.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.1 | 0.1
Realized and unrealized gains | 0.0 | 0.0
Purchases | 0.0 | 0.0
Sales | (0.1) | 0.0
Fair value of plan assets at end of year | 0.0 | 0.1
United States | Level 3 [Member] | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
United States | Level 3 [Member] | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.1 | 0.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.1 |
Fair value of plan assets at end of year | 0.0 | 0.1
France |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 3.2 | 6.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 3.2 | 6.1
Fair value of plan assets at end of year | 2.1 | 3.2
France | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.2 | 1.2
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.2 |
Fair value of plan assets at end of year | 0.9 | 1.2
France | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.0 | 1.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.0 |
Fair value of plan assets at end of year | 0.6 | 1.0
France | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.9 | 0.9
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.9 |
Fair value of plan assets at end of year | 0.5 | 0.9
France | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.1 | 0.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.1 |
Fair value of plan assets at end of year | 0.1 | 0.1
France | Level 1 [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 2.2 | 2.2
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 2.2 |
Fair value of plan assets at end of year | 1.5 | 2.2
France | Level 1 [Member] | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.2 | 1.2
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.2 |
Fair value of plan assets at end of year | 0.9 | 1.2
France | Level 1 [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.0 | 1.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.0 |
Fair value of plan assets at end of year | 0.6 | 1.0
France | Level 1 [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 1 [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 1 [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 1 [Member] | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 2 [Member] |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 1.0 | 1.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 1.0 |
Fair value of plan assets at end of year | 0.6 | 1.0
France | Level 2 [Member] | Cash and cash equivalents |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 2 [Member] | Domestic large cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 2 [Member] | Domestic small cap |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 2 [Member] | International |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.0 |
Fair value of plan assets at end of year | 0.0 | 0.0
France | Level 2 [Member] | Fixed income securities |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.9 | 0.9
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.9 |
Fair value of plan assets at end of year | 0.5 | 0.9
France | Level 2 [Member] | Alternative investments |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Fair value of plan assets | 0.1 | 0.1
U.S. Level 3 Asset Reconciliation |  |
Fair value of plan assets at beginning of year | 0.1 |
Fair value of plan assets at end of year | $ 0.1 | $ 0.1

X
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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- Definition Amount, measured using unobservable input, of decrease in plan asset of defined benefit plan from sale. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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