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Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Beginning Balance |  |  |  | $ 65.6 |  |
Additions | [1] |  |  | 0.9 |  |
Amortization |  | $ (1.3) | $ (1.3) | (4.1) | $ (3.8) |
Ending Balance |  | 62.4 |  | 62.4 |  |
Accumulated Amortization |  | 13.4 |  | 13.4 |  | $ 9.3
Estimated Annual Amortization Expense for Definite-Lived Intangible Assets [Abstract] |  |  |  |  |  |
Remainder of 2017 |  | 1.5 |  | 1.5 |  |
2018 |  | 5.3 |  | 5.3 |  |
2019 |  | 4.9 |  | 4.9 |  |
2020 |  | 4.7 |  | 4.7 |  |
2021 |  | 4.6 |  | 4.6 |  |
Thereafter |  | 41.4 |  | 41.4 |  |
Intangible Assets [Abstract] |  |  |  |  |  |
Total Intangible Assets |  | 79.0 |  | 79.0 |  | $ 82.2
Total Intangible Assets, Additions | [2] |  |  | 0.9 |  |
Total Intangible Assets, Amortization |  | (1.3) | $ (1.3) | $ (4.1) | $ (3.8) |
Weighted Average [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Remaining Useful Life (Years) |  |  |  | 19 years |  |
Trademarks and Trade Names [Member] |  |  |  |  |  |
Indefinite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Beginning Balance |  |  |  | $ 16.6 |  |
Additions | [2] |  |  | 0.0 |  |
Ending Balance |  | 16.6 |  | 16.6 |  |
Customer Relationships [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Beginning Balance |  |  |  | 59.3 |  |
Additions | [2] |  |  | 0.0 |  |
Amortization |  |  |  | (3.4) |  |
Ending Balance |  | 55.9 |  | $ 55.9 |  |
Remaining Useful Life (Years) |  |  |  | 20 years |  |
Intangible Assets [Abstract] |  |  |  |  |  |
Total Intangible Assets, Amortization |  |  |  | $ (3.4) |  |
Developed Technology and Other [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Beginning Balance | [1] |  |  | 6.3 |  |
Additions | [1],[2] |  |  | 0.9 |  |
Amortization | [1] |  |  | (0.7) |  |
Ending Balance | [1] | $ 6.5 |  | 6.5 |  |
Intangible Assets [Abstract] |  |  |  |  |  |
Total Intangible Assets, Amortization | [1] |  |  | $ (0.7) |  |
Developed Technology and Other [Member] | Minimum [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Remaining Useful Life (Years) |  |  |  | 1 year |  |
Developed Technology and Other [Member] | Maximum [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Remaining Useful Life (Years) |  |  |  | 11 years |  |
Developed Technology and Other [Member] | Weighted Average [Member] |  |  |  |  |  |
Definite-Lived Intangible Assets [Roll Forward] |  |  |  |  |  |
Remaining Useful Life (Years) |  |  |  | 7 years |  |
[1] | Developed Technology and Other includes patents, non-compete agreements, land easements and trade names.
[2] | Additions resulting from the September 1, 2017, acquisition of Tonka Water. (See Note 3. Acquisitions.)

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