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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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No definition available.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-based Compensation (Exercise Price Range) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of options (in share)	3,383,972	3,375,909	85,901	111,571
Options outstanding, weighted-average exercise price (in dollars per share)	$ 5.32	$ 5.44	$ 34.85	$ 38.92
Options outstanding, weighted-average remaining contractual life (years)	8 years
Exercisable options, number of options (in shares)	83,972	75,909	67,404
Exercisable options, weighted-average exercise price (in dollars per share)	$ 26.02
Under $50.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, upper limit (in dollars per share)	$ 50.00
Options outstanding, number of options (in share)	3,371,834
Options outstanding, weighted-average exercise price (in dollars per share)	$ 4.80
Options outstanding, weighted-average remaining contractual life (years)	8 years 9 days
Exercisable options, number of options (in shares)	71,834
Exercisable options, weighted-average exercise price (in dollars per share)	$ 5.45
$80.01 - $120.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise rice range, lower limit (in dollars per share)	80.01
Exercise price range, upper limit (in dollars per share)	$ 120.00
Options outstanding, number of options (in share)	8,831
Options outstanding, weighted-average exercise price (in dollars per share)	$ 101.30
Options outstanding, weighted-average remaining contractual life (years)	1 year 2 months 3 days
Exercisable options, number of options (in shares)	8,831
Exercisable options, weighted-average exercise price (in dollars per share)	$ 101.30
$220.01 - $279.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise rice range, lower limit (in dollars per share)	220.01
Exercise price range, upper limit (in dollars per share)	$ 279.00
Options outstanding, number of options (in share)	3,307
Options outstanding, weighted-average exercise price (in dollars per share)	$ 271.82
Options outstanding, weighted-average remaining contractual life (years)	1 month 7 days
Exercisable options, number of options (in shares)	3,307
Exercisable options, weighted-average exercise price (in dollars per share)	$ 271.82
Restricted Stock \| Minimum
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Grants scheduled vesting period	3 years	3 years
Restricted Stock \| Maximum
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Grants scheduled vesting period	5 years	5 years
Employee Stock Option
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable options, weighted-average exercise price (in dollars per share)		$ 4.79
Dividend yield		0.00%
Expected volatility		36.59%
Risk-free rate		1.28%
Expected option life		5 years