Supplemental Balance Sheet Data - Inventories (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Inventories by major class:
Raw materials	$ 33.4	$ 32.8
Work in progress	24.8	26.4
Finished goods	76.4	67.3
Supplies and other	5.2	5.2
Inventories, gross	139.8	131.7
Adjust FIFO inventories to LIFO cost	(8.4)	(8.9)
Total	131.4	122.8
FIFO values of inventories valued on the LIFO method	110.6	$ 102.2
Maximum
Inventories by major class:
Decrease in LIFO inventory (less than)	$ 0.1

The effect of liquidating LIFO (last in first out) inventory layers on income.

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The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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