XML 14 R39.htm IDEA: XBRL DOCUMENT v2.4.1.9

Components of net periodic benefit cost (Tables)

3 Months Ended

Mar. 31, 2015

Components of net periodic benefit cost [Abstract]

Schedule of net periodic benefit cost

	Pension Benefits
	Three months ended March 31,
	2015			2014
Service cost	$	1,704		$	1,587
Interest cost	3,388			2,640
Expected return on plan assets	(5,494		)	(3,397		)
Amortization of prior service costs	25			9
Amortization of net loss	620			787
Net periodic benefit cost	$	243		$	1,626

	Other Postretirement Benefits ("OPEB")
	Three months ended March 31,
	2015			2014
Service cost	$	562		$	677
Interest cost	1,591			1,511
Amortization of prior service cost	(961		)	(961		)
Amortization of net loss	865			1,024
Net periodic benefit cost	$	2,057		$	2,251

X

- Details

Name:	cenx_ComponentsOfNetPeriodicBenefitCostAbstract
Namespace Prefix:	cenx_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- 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=35743120&loc=d3e1928-114920

+ Details

Name:	us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration