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Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan		31,136	33,503	33,938
Weighted Average exercise Price of Options Outstanding		$ 84.50	$ 96.22	$ 107.37
Stock options award, expiration		10 years
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to unvested options		$ 25
Maturity period of weighted average period of compensation expenses		6 months
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period		3 years
Percentage holding for stock options exercise price		10.00%
Minimum | Incentive Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option		100.00%
Minimum | Incentive Stock Option | Stockholders
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option		110.00%
Minimum | Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units award, requisite service period		3 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period		4 years
Maximum | Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units award, requisite service period		4 years
2013 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of shares reserve for issuance under amended Equity Plan	55,555
Number of shares issuable under Equity plan	73,412
Number of shares outstanding under Equity plan		30,914
Weighted Average exercise Price of Options Outstanding		$ 73.14
Shares reserved for future		36,511
Options granted		0	2,220
Two Thousand And Four Stock Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan		222
Weighted Average exercise Price of Options Outstanding		$ 1,665.68

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