Share-based Compensation - ESPP (Details) - Employee Stock Purchase Plan [Member] - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
Jul. 31, 2019	Dec. 31, 2019	Jun. 30, 2018
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Number of shares authorized			2,300,000
Purchase election as percentage of compensation		15.00%
Purchase price as percentage of fair value		85.00%
Share-based compensation recognized cost		$ 0.2
Shares purchased	79,940
Price per share	$ 4.37

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Number of shares authorized for issuance under share-based payment arrangement.

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Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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