Employee Benefit Plans (Summary of Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2016	$ 19,164
2107	20,320
2018	21,833
2019	21,341
2020	21,461
Thereafter	106,953
Total	211,072
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2016	8,356
2107	8,341
2018	8,344
2019	8,281
2020	8,245
Thereafter	38,178
Total	$ 79,745