Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	14. SUBSEQUENT EVENTS On January 28, 2019, the Company closed a follow-on underwritten public offering of 3,950,000 ordinary shares for gross proceeds of $150.1 million, and on February 26, 2019, the Company closed on the sale of an additional 592,500 ordinary shares pursuant to the underwriters’ option (on the same terms and conditions as the initial closing) for gross proceeds of an additional $22.5 million (collectively, the “January 2019 Offering”). The net proceeds to the Company from the January 2019 Offering are expected to be approximately $161.6 million, after deducting underwriting discounts and commissions and estimated offering expenses.

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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