Pension and Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2016

General Discussion Of Pension And Other Postretirement Benefits [Abstract]

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

	Three Months Ended March 31,
					Other
	Pension Benefits				Postretirement Benefits
		2016		2015		2016		2015
Service cost	$	670	$	773	$	4	$	5
Interest cost		1,111		1,262		39		50
Expected return on plan assets		(1,344)		(1,402)		—		—
Actuarial loss amortization		808		881		15		26
Prior service cost amortization		(25)		(26)		—		—
Net periodic benefit cost	$	1,220	$	1,488	$	58	$	81