Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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The number of positions eliminated during the period as a result of restructuring activities.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Restructuring Expenses (Details) $ in Millions		3 Months Ended	12 Months Ended
Restructuring Expenses (Details) $ in Millions	Feb. 15, 2017 Employee	Jun. 30, 2016 Employee	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of positions eliminated \| Employee	100	36
Restructuring payments				$ 1.7
Restructuring expenses				$ 1.7
Employee severance
Restructuring Cost and Reserve [Line Items]
Restructuring payments			$ 3.7
Facility closing
Restructuring Cost and Reserve [Line Items]
Facility-related costs incurred			4.2
Restructuring payments			0.6
Accrued compensation \| Facility closing
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, current			$ 0.4