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Employee benefit plans (Tables)

3 Months Ended

Mar. 31, 2013

Employee Benefit Plans [Abstract]

Schedule of net benefit costs

Components of net periodic benefit cost for the Company's pension and other postretirement benefit plans were as follows:

							Other
							Postretirement
	Pension Benefits						Benefits
Three Months Ended March 31,	2013			2012			2013			2012
	(In thousands)
Components of net periodic benefit cost:
Service cost	$	40		$	345		$	504		$	412
Interest cost	4,018			4,554			940			1,143
Expected return on assets	(5,083		)	(5,886		)	(1,107		)	(1,244		)
Amortization of prior service cost (credit)	18			(21		)	(364		)	(272		)
Amortization of net actuarial loss	1,864			1,681			671			526
Amortization of net transition obligation	—			—			—			532
Net periodic benefit cost, including amount capitalized	857			673			644			1,097
Less amount capitalized	110			234			29			138
Net periodic benefit cost	$	747		$	439		$	615		$	959

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- Definition

Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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