Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The amount of consideration recognized during the period under a development, licensing and supply agreement entered into with a customer.

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Other Expense Items (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($) $ / shares	Mar. 31, 2016 USD ($) $ / shares	Dec. 31, 2016	Feb. 17, 2016	Jun. 30, 2013 USD ($)
Other Income and Expenses [Abstract]
Development income	$ (0.4)	$ (0.4)
Nonrefundable payment from customer	14.0				$ 20.0
Unearned income, current	1.5
Unearned income, noncurrent	$ 12.5
Summary of Investment Holdings [Line Items]
Earnings Per Share, Diluted \| $ / shares	$ 0.81	$ 0.30
Venezuela currency devaluation	$ 0.0	$ 2.7
VENEZUELA
Summary of Investment Holdings [Line Items]
Foreign currency exchange rate, remeasurement			6.3	10.0
Estimate of possible pre-tax charge	$ 15.0
Minimum [Member] \| VENEZUELA
Summary of Investment Holdings [Line Items]
Earnings Per Share, Diluted \| $ / shares	$ 0.12
Maximum [Member] \| VENEZUELA
Summary of Investment Holdings [Line Items]
Earnings Per Share, Diluted \| $ / shares	$ 0.15