Subsequent Events	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	20. Subsequent Events In January 2020, the Company implemented changes to its organizational structure to create a leaner company focused on advancing SGT-001. In connection with the restructuring, the Company made changes to its management team and reduced headcount by approximately 30 percent. The Company expects to substantially complete the restructuring in the first quarter of 2020. The Company estimates total restructuring costs of approximately $2.1 million related to severance and other employee termination benefits. The Company expects that approximately $1.2 million would be paid during the three months ended March 31, 2020 and approximately $0.9 million would be paid during the remainder of 2020.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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