7. Stockholders' Equity (Details) - Common Stock $ / shares in Units, $ in Thousands	1 Months Ended
May 30, 2018 USD ($) $ / shares shares
Number of shares repurchased \| shares	1,190,420
Average price paid per share \| $ / shares	$ 3.89
Approximate value of shares that may yet be purchased \| $	$ 15,366
Plan expiration date	Feb. 28, 2019

Number of shares that have been repurchased during the period and are being held in treasury.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration