Global Health Care Medical Costs Payable (Details) (Accident and health insurance [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accident and health insurance [Member]
Liability For Unpaid Claims And Claims Adjustment Expense [Line Items]
Incurred but not yet reported	$ 1,830	$ 1,777
Reported claims in process	439	288
Phyician incentives and other medical expense payable	139	115
Medical costs payable	$ 2,408	$ 2,180	$ 2,050

Liability for other medical expense payable included in medical claims payable.

No definition available.

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- Definition

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a),(b),(c)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Definition

Estimated costs as of the balance sheet date of settling insured claims and costs incurred in the claims settlement process for claims that have not yet been submitted to the insurance company for reimbursement.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section W

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.W)

-URI http://asc.fasb.org/extlink&oid=27015833&loc=d3e570705-122907

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Costs of settling insured claims and costs incurred in the claims settlement process for the specified year specifically for claims that have already been submitted to the insurance company for reimbursement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant