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Employee benefit plans (Tables)

9 Months Ended

Sep. 30, 2012

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 September 30,	2012			2011			2012			2011
	(In thousands)
Components of net periodic benefit cost:
Service cost	$	349		$	35		$	437		$	361
Interest cost	4,407			4,706			943			1,175
Expected return on assets	(5,865		)	(5,679		)	(1,222		)	(1,263		)
Amortization of prior service credit	(22		)	(54		)	(534		)	(669		)
Amortization of net actuarial loss	1,887			917			356			430
Amortization of net transition obligation	—			—			531			532
Curtailment gain	(1,023		)	—			—			—
Net periodic benefit cost, including amount capitalized	(267		)	(75		)	511			566
Less amount capitalized	185			323			314			(41		)
Net periodic benefit cost	$	(452	)	$	(398	)	$	197		$	607
							Other
							Postretirement
	Pension Benefits						Benefits
Nine Months Ended September 30,	2012			2011			2012			2011
	(In thousands)
Components of net periodic benefit cost:
Service cost	$	1,044		$	1,689		$	1,310		$	1,083
Interest cost	13,223			14,625			3,124			3,525
Expected return on assets	(17,596		)	(17,106		)	(3,667		)	(3,789		)
Amortization of prior service cost (credit)	(64		)	33			(1,078		)	(2,007		)
Amortization of net actuarial loss	5,670			3,509			1,769			688
Amortization of net transition obligation	—			—			1,594			1,594
Curtailment (gain) loss	(1,023		)	1,218			—			—
Net periodic benefit cost, including amount capitalized	1,254			3,968			3,052			1,094
Less amount capitalized	615			858			635			(136		)
Net periodic benefit cost	$	639		$	3,110		$	2,417		$	1,230

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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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