Commitments and Contingencies Commitments and Contingencies (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Number of repair facilities with labor union collective bargaining agreements	2
Gain Contingency, Unrecorded Amount	$ 25.0
Loss Contingency, Damages Sought, Value	10.0
Loss Contingency Accrual	$ 12.2	$ 12.3