CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 718.9us-gaap_ProfitLoss	$ 279.7us-gaap_ProfitLoss
Foreign currency translation adjustments	(23.2)	3.0
Pension liability adjustment	(5.9)	0
Net unrealized gains (losses) related to cash flow hedges:
Unrealized holding gains (losses)	406.9	(18.6)
Tax benefit	9.9	3.7
Unrealized gains (losses), net of tax expense (benefit) of [$x.x] and ($0.2) for the three months ended September 30, 2014, and 2013, respectively, and [$x.x] and $0 for the nine months ended September 30, 2014, and 2013, respectively.	(416.8)	14.9
Reclassification adjustment for (gains) losses included in net income	(69.2)	1.9
Tax (benefit)	(0.5)	(0.3)
Reclassification adjustment for (gains) losses included in net income, net of tax (expense) benefit of [$x.x] and $0.3 for the three months ended September 30, 2014 and 2013, respectively, and [$x.x] and $6.5 for the nine months ended September 30, 2014 and 2013, respectively.	(69.7)	1.6
Net unrealized gains (losses) on marketable securities available for sale:
Unrealized holding gains (losses)	(77.1)	84.3
Tax (expense) benefit	26.5	(29.0)
Unrealized gains (losses), net of tax expense (benefit) of [$x.x] and $58.5 for the three months ended September 30, 2014 and 2013, respectively, and [$x.x] and $78.4 for the nine months ended September 30, 2014 and 2013, respectively.	(50.6)	55.3
Reclassification adjustment for (gains) losses included in net income	(0.6)	1.4
Tax expense (benefit)	0.2	(0.5)
Reclassification adjustment for (gains) losses included in net income, net of tax	(0.4)	0.9
Total other comprehensive income (loss)	267.0	45.9
Comprehensive income	$ 985.9	$ 325.6

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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