Commitments and Contingencies - Product Liability (Details) - Product liability - Bair Hugger	9 Months Ended	12 Months Ended
Sep. 30, 2018 USD ($) case item	Dec. 31, 2017 item
Product Liability Litigation
Number of plaintiffs	4,955	4,270
Accrued loss contingency reserve \| $	$ 0
Number of total claims dismissed \| case	61
U.S. District Court for the Western District of Tennessee
Product Liability Litigation
Number of lawsuits filed	1

Amount of loss contingency liability.

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The total number of new claims filed pertaining to a loss contingency during the period.

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-Topic 450
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-Section 50
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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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