Income Taxes - NOL and Tax Credits (Details) $ in Thousands	12 Months Ended
Mar. 31, 2018 USD ($)
U.S. research credits
Tax credit carryforwards
Tax Credits	$ 1,253
Fiscal Year of Expiration	Dec. 31, 2023
Texas franchise tax credits
Tax credit carryforwards
Tax Credits	$ 2,955
Fiscal Year of Expiration	Dec. 31, 2026

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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Expiration date of the tax credit carryforward, in CCYY-MM-DD format.

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