Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Pension Plans
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2016	$ 27,031
2017	27,341
2018	28,230
2019	29,159
2020	29,777
2021-2025	156,982
Postretirement Benefit Plan
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2016	3,418
2017	3,307
2018	3,155
2019	3,036
2020	3,024
2021-2025	14,657
Expected Medicare Part D Subsidies [Abstract]
2016	24
2017	25
2018	29
2019	25
2020	25
2021-2025	153
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2016	3,394
2017	3,282
2018	3,126
2019	3,011
2020	2,999
2021-2025	$ 14,504

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No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in the five fiscal years thereafter (the aggregate net amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

No definition available.