Employee Benefit Plans - Narrative (Details) $ in Millions	6 Months Ended
	Jun. 30, 2016 USD ($)
SERP
Defined Benefit Plan Disclosure [Line Items]
Contributions to benefit plan	$ 0.5
Estimated future contributions	0.6
Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Contributions to benefit plan	1.2
Minimum | Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions	5.0
Maximum | Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions	$ 10.0