Warrants, Restricted Stock, Restricted Stock Units, Options and Option Matching Rights - Schedule of Stock Option Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, beginning balance (shares)	13,300	33,600	56,600
Exercised (shares)	(1,700)	(2,000)	(18,000)
Forfeited (shares)	(11,600)	(18,300)	(5,000)
Options outstanding, ending balance (shares)	0	13,300	33,600	56,600
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Options outstanding, beginning balance (usd per share)	$ 26.03	$ 68.92	$ 48.50
Exercised (usd per share)	15.00	7.95
Options outstanding, ending balance (usd per share)	$ 0.00	$ 26.03	$ 68.92	$ 48.50
Options outstanding, weighted average remaining contractual life (in years)	0 years	8 months 27 days	1 year 1 month 10 days	2 years 7 months 10 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Options outstanding, beginning balance (usd per share)	$ 15.00	$ 7.95	$ 7.95
Exercised (usd per share)			7.95
Forfeited (usd per share)	24.75	14.85	14.85
Options outstanding, ending balance (usd per share)		15.00	7.95	$ 7.95
Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Options outstanding, beginning balance (usd per share)	40.05	131.10	131.10
Exercised (usd per share)			9.90
Forfeited (usd per share)	$ 40.05	131.10	82.95
Options outstanding, ending balance (usd per share)		$ 40.05	$ 131.10	$ 131.10

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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Number of share options (or share units) exercised during the current period.

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