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Fair Value Measurements (Details 1) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |  |  |  |  |  |
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Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 Fair Value, Measurements, Recurring Venture capital investments | Jun. 30, 2014 Fair Value, Measurements, Recurring Venture capital investments | Dec. 31, 2013 Fair Value, Measurements, Recurring Venture capital investments | Sep. 30, 2013 Fair Value, Measurements, Recurring Venture capital investments | Jun. 30, 2013 Fair Value, Measurements, Recurring Venture capital investments | Dec. 31, 2012 Fair Value, Measurements, Recurring Venture capital investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |  |  |
Fair value, beginning of period |  |  |  |  | $ 16.7 | $ 21.1 | $ 21.9 | $ 27.6 | $ 23.5 | $ 20.3
Unrealized gains included in earnings | 0.3 | 3.8 | 5.3 | 10.5 |  |  |  |  |  |
Unrealized losses included in earnings | (3.8) | 0 | (5.1) | (2.0) |  |  |  |  |  |
Purchases | 0 | 0.3 | 0 | 0.3 |  |  |  |  |  |
Settlements | (0.9) | 0 | (5.4) | (1.5) |  |  |  |  |  |
Fair value, end of period |  |  |  |  | $ 16.7 | $ 21.1 | $ 21.9 | $ 27.6 | $ 23.5 | $ 20.3

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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 + Details
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