Benefit Plans and Other Postretirement Benefits Benefits Plans and Other Postretirement Benefits, Fair Value Hierarchy (Details)	12 Months Ended
Dec. 31, 2013
Commingled funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Notice period for investment redemption (in days)	1
Commingled funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Notice period for investment redemption (in days)	90
Real estate funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Notice period for investment redemption (in days)	45
Real estate funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Notice period for investment redemption (in days)	90

States the notice requirement (for example, 30 to 60 days) the entity is required to deliver before it can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 6A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=SL6742756-110258

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareInvestmentRedemptionNoticePeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration