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v3.19.3.a.u2

Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Cash Equivalents and Short-term Investments [Abstract] |  |  |
Short-term investments | $ 1.6 | $ 3.8 |
Unrealized holding gains and losses on short-term bank investments | $ 0.0 |  |
Trade Accounts Receivable [Abstract] |  |  |
Past due threshold for individual collectability review | 90 days |  |
Allowance for doubtful accounts | $ 12.9 | 3.2 |
Property, Plant and Equipment [Abstract] |  |  |
Initial term of long term evergreen contracts | 10 years |  |
Investment in Joint Ventures [Abstract] |  |  |
Equity method investment | $ 16.1 |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Operating liabilities | 11.9 |  |
Right-of-use assets | 44.8 |  |
Operating Income (Loss) [Abstract] |  |  |
Marketing and administrative expenses | (187.5) | (178.6) | $ (180.7)
Other deductions | $ (8.2) | (1.5) | $ (6.2)
Buildings [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 3.00% |  |
Buildings [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 6.67% |  |
Machinery and Equipment [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 6.67% |  |
Machinery and Equipment [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 12.50% |  |
Furniture and Fixtures [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 8.00% |  |
Furniture and Fixtures [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 12.50% |  |
Computer Equipment and Software-related Assets [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 12.50% |  |
Computer Equipment and Software-related Assets [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Annual rates of depreciation | 25.00% |  |
PCC Production Facilities [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Estimated useful life | 15 years |  |
Machinery and Equipment for Natural Stone Mining and Processing Plants and Chemical Plants [Member] |  |  |
Property, Plant and Equipment [Abstract] |  |  |
Estimated useful life | 15 years |  |
ASU 2016-02 [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Operating liabilities |  | 61.4 |
Right-of-use assets |  | 50.5 |
Deferred charges |  | 10.9 |
ASU 2018-02 [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income |  | 0.0 |
ASU 2018-02 [Member] | Accumulated Other Comprehensive Loss [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income | $ (10.9) | (10.9) |
ASU 2018-02 [Member] | Retained Earnings [Member] |  |  |
Recently Adopted Accounting Standards [Abstract] |  |  |
Reclassification of certain tax effects from accumulated other comprehensive income | $ 10.9 | $ 10.9 |

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