Common Stock	6 Months Ended
Jun. 30, 2019
Preferred Stock Common Stock And Warrants [Abstract]
Common Stock	11. Common Stock Common Stock Outstanding As of June 30, 2019, there were 65,154,729 shares of our common stock outstanding. On November 3, 2017, we entered into an At Market Sales Agreement (“2017 ATM Agreement”) with Cowen and Company, LLC (“Cowen”) under which we may offer and sell from time to time at our sole discretion, shares of our common stock having an aggregate offering price up to $150 million through Cowen as our sales agent. We pay Cowen a commission of up to 3% of the gross sales proceeds of any common stock sold through Cowen under the 2017 ATM Agreement. For the six months ended June 30, 2019, we received net cash proceeds of $13.9 million resulting from sales of 1,386,906 shares of our common stock. As of June 30, 2019, we have $118.6 million remaining under the 2017 ATM Agreement.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI http://asc.fasb.org/topic&trid=2208762

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