CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowances	$ 2,600	$ 3,097
Redeemable convertible preferred stock, Par value (in dollars per share)	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, Shares authorized (in shares)	928,676,000	928,676,000
Redeemable convertible preferred stock, Shares issued (in shares)	308,373,000	308,373,000
Redeemable convertible preferred stock, Shares outstanding (in shares)	308,373,000	308,373,000
Common Stock, Par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares authorized (in shares)	1,932,500,000	1,932,500,000
Common Stock, Shares issued (in shares)	127,371,000	127,298,000
Common Stock, Shares outstanding (in shares)	127,371,000	127,298,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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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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