Basis of Presentation (Unaudited) (Details 4) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other Assets, Noncurrent	$ 1,152	$ 1,157
Long-term Debt and Capital Lease Obligations	$ 6,387	6,386
ASU 2015-03 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other Assets, Noncurrent		(30)	$ (27)
Long-term Debt and Capital Lease Obligations		$ (30)	$ (27)

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section H

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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