Contingencies (Federal Government's Lawsuit) (Details) - Federal Governments Lawsuit [Member] - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Aug. 31, 2006	Dec. 31, 2014
Loss Contingencies [Line Items]
Disclosure period	10 years
Implementation of Corrective Communications [Member]
Loss Contingencies [Line Items]
Provision related to litigation recorded		$ 36

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Name:	us-gaap_LossContingencyAccrualProvision
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration