401 (k) Savings Plan	12 Months Ended
Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract]
401(k) Savings Plan	11. 401(k) Savings Plan The Company established a defined‑contribution savings plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”) in November 2016. The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pretax basis. The Company contributed $1.1 million, $0.6 million and $0.5 million to the 401(k) Plan for the year ended December 31, 2019, 2018 and 2017, respectively.

The entire disclosure for pension and other postretirement benefits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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