Pension and postretirement benefits (Tables)

3 Months Ended

Mar. 31, 2017

Pension Plans, Defined Benefit [Member]

Schedule Of Net Benefit Costs Table Text Block

		Pension Plan				Benefit Restoration Plans
		Quarters ended March 31,				Quarters ended March 31,
(In thousands)		2017		2016		2017		2016
Interest cost	$	6,120	$	6,291	$	352	$	348
Expected return on plan assets		(10,186)		(9,623)		(502)		(538)
Amortization of net loss		5,054		4,880		411		331
Total net periodic pension cost (benefit)	$	988	$	1,548	$	261	$	141

Other Postretirement Benefit Plans Defined Benefit [Member]

Schedule Of Net Benefit Costs Table Text Block

		Quarters ended March 31,
(In thousands)		2017		2016
Service cost	$	256	$	289
Interest cost		1,426		1,505
Amortization of prior service cost		(950)		(950)
Amortization of net loss		142		275
Total postretirement cost	$	874	$	1,119