Income Taxes Income (Loss) Before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income (Loss) Before Income Taxes [Line Items]
Total income before income taxes	$ 2,145	$ 1,761	$ 1,884
Ireland
Income (Loss) Before Income Taxes [Line Items]
Total income before income taxes	(608)	(332)	184
Foreign
Income (Loss) Before Income Taxes [Line Items]
Total income before income taxes	$ 2,753	$ 2,093	$ 1,700

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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