Fair Value Measurement - Carrying Value and Estimated Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Fair Value Measurement
Long-term borrowings	$ 126.4	$ 153.8
Restated Credit Facility, net of original discount on borrowings and deferred financing costs
Fair Value Measurement
Long-term borrowings		151.0
Restated Credit Facility, net of original discount on borrowings and deferred financing costs | Carrying Amount
Fair Value Measurement
Long-term borrowings	123.8	151.0
Restated Credit Facility, net of original discount on borrowings and deferred financing costs | Fair Value
Fair Value Measurement
Long-term borrowings	123.8	151.0
Other borrowings
Fair Value Measurement
Long-term borrowings	2.6	2.8
Other borrowings | Carrying Amount
Fair Value Measurement
Long-term borrowings	2.6	2.8
Other borrowings | Fair Value
Fair Value Measurement
Long-term borrowings	$ 2.6	$ 2.8