Employee Benefit Plans - Narrative (Details) $ in Millions		12 Months Ended
	Sep. 14, 2016 USD ($)	Dec. 31, 2016 USD ($) entrant	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of new entrants since plans were frozen | entrant		0
Multi-employer defined benefit plan, contributions		$ 0.5	$ 0.4	$ 0.4
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement of accumulated benefits		2.7	2.2
Increase in funded status		0.4
Funded status at end of year		(4.3)	(4.7)
Actual return on plan assets		1.4	(1.8)
Employer contributions		1.9	0.0
Interest cost		1.2	1.7	1.8
Actuarial loss		1.7	(2.0)
Increase in projected benefit obligation		2.0
Favorable demographic experience		0.3
Settlement charge		$ (1.3)	(1.6)	0.0
Average future life expectancy		20 years 5 months 2 days
Group annuity contract discontinuance		$ 0.0	1.3
Other Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement of accumulated benefits		0.0	0.0
Funded status at end of year		(2.6)	(3.0)
Actual return on plan assets		0.0	0.0
Employer contributions		0.1	0.2
Interest cost		0.2	0.1	0.1
Actuarial loss		(0.5)	0.1
Settlement charge		$ 0.0	0.0	$ 0.0
Remaining service life		4 years 7 months 2 days
Group annuity contract discontinuance		$ 0.0	$ 0.0
Estimated future employer contributions in next fiscal year		$ 0.2
Minimum
Defined Benefit Plan Disclosure [Line Items]
Unrecognized actuarial losses in accumulated other comprehensive income	$ 17.0
Settlement of accumulated benefits	4.0
Maximum
Defined Benefit Plan Disclosure [Line Items]
Unrecognized actuarial losses in accumulated other comprehensive income	19.0
Settlement of accumulated benefits	$ 6.0