Condensed Consolidating Financial Statements (Narrative) (Details) - USD ($)	Dec. 31, 2015	Aug. 18, 2015	May. 26, 2015
Condensed Financial Statements, Captions [Line Items]
Ownership interest of subsidiary	100.00%
Senior notes
Condensed Financial Statements, Captions [Line Items]
Debt issued		$ 2,000,000,000.0
Senior notes | 4.0% Senior Notes due in 2025
Condensed Financial Statements, Captions [Line Items]
Debt issued			$ 700,000,000
Interest rate			4.00%
Senior notes | 2.5% Senior Notes due in 2018
Condensed Financial Statements, Captions [Line Items]
Debt issued		$ 400,000,000
Interest rate		2.50%
Senior notes | 3.3% Senior Notes due in 2020
Condensed Financial Statements, Captions [Line Items]
Debt issued		$ 700,000,000
Interest rate		3.30%
Senior notes | 4.4% Senior Notes due in 2026
Condensed Financial Statements, Captions [Line Items]
Debt issued		$ 900,000,000
Interest rate		4.40%