Employee Benefit Plans - Annual Retirement Plan Expense Assumptions (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Discount rate		5.08%	4.27%
Long-term rate of return on plan assets		5.25%	4.65%
Increase in compensation levels		2.00%	3.30%
Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.01%
Long-term rate of return on plan assets	4.10%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.53%
Long-term rate of return on plan assets	6.10%