Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	(19) Subsequent Events In January 2019, the Company completed a follow-on public offering in which the Company sold 2,645,000 shares of its common stock, which included 345,000 shares sold pursuant to the exercise by the underwriters of an option to purchase additional shares, at a public offering price of $55.25 per share. The Company received aggregate proceeds of $139.7 million, after deducting underwriting discounts and commission.

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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