Fair Value Of Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Feb. 15, 2017
contingent interest payment		$ 7.7
Fair value assumptions expected volatility rate	26.00%
fair value assumptions credit spread	4.00%
Convertible Debt, Fair Value Disclosures	$ 2,800.0
Minimum [Member]
fair value hypothetical increase decrease in volatility rate	21.00%
fair value hypothetical increase decrease in credit spread	3.00%
Maximum [Member]
fair value hypothetical increase decrease in volatility rate	31.00%
fair value hypothetical increase decrease in credit spread	5.00%
Due 2025 [Member]
Convertible Debt, Fair Value Disclosures	$ 514.1
Due 2023 [Member]
Convertible Debt, Fair Value Disclosures	$ 764.1

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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