Benefit Plans - Defined Benefit Plans - Nonqualified Defined Benefit Pension Plan (Details) - Supplemental Retirement Plan $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) item
Supplemental Retirement Plan
Combined number of active and retired/terminated participants in the defined benefit plan | item	53
Vesting period of defined benefit stated amount, minimum	9 years
Plan assets associated with the plan | $	$ 0