Financial Instruments (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Proceeds from Marketable Debt Securities
Proceeds from maturities and sales	$ 7,378.9	$ 4,063.0	$ 2,718.9
Realized gains	3.3	1.5	0.7
Realized losses	$ (4.3)	$ (3.5)	$ (0.5)

Proceeds from marketable debt securities.

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

+ Details

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

The cash inflow associated with the sale or maturity (principal being due) of securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

+ Details

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