Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Common stock, par value (in usd per share)	$ 0.0000001	$ 0.0000001
Common stock, shares authorized (shares)	350,000,000	350,000,000
Common stock, shares outstanding (shares)	86,098,474	85,832,454
Common stock, shares issued (shares)	86,098,474	85,832,454
Variable interest entity, assets	$ 47,000	$ 48,300
Variable interest entity, liabilities	$ 942	$ 1,200

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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