Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Convertible preferred stock, par value	$ 0.0001	$ 0.0001
Convertible preferred stock, authorized (in shares)	10,000,000	17,371,402
Convertible preferred stock, issued (in shares)	0	14,500,938
Convertible preferred stock, outstanding (in shares)	0	14,500,938
Convertible preferred stock, liquidation value	$ 0	$ 195,317
Class A
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	1,500,000,000	177,000,000
Common stock, issued (in shares)	30,042,687	0
Common stock, outstanding (in shares)	30,042,687	0
Class B
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	175,000,000	175,000,000
Common stock, issued (in shares)	160,097,378	67,095,128
Common stock, outstanding (in shares)	160,097,378	67,095,128
Class C
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	500,000,000	2,000,000
Common stock, issued (in shares)	0	0
Common stock, outstanding (in shares)	0	0

Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=65877616&loc=d3e177068-122764

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