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Convertible Preferred Stock, Shares Issued upon Conversion as Percent of Common Stock Outstanding

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Certain Relationships and Related Party Transactions (Details) - USD ($)			12 Months Ended
	Jan. 30, 2018	Jan. 23, 2018	Dec. 31, 2018	Dec. 31, 2017
Wipro
Related Party Transaction [Line Items]
Capitalized costs for internally developed software services received			$ 2,300,000
Accounts payable, related parties			5,000,000	$ 2,200,000
Accounts receivable, related parties				0
Wipro \| Asset impairment charge
Related Party Transaction [Line Items]
Capitalized costs for internally developed software services received			2,100,000
Wipro \| Technology Related Services
Related Party Transaction [Line Items]
Expenses from transactions with related party			$ 12,300,000	$ 5,600,000
Securities Purchase Agreement \| Series A Preferred Stock
Related Party Transaction [Line Items]
Number of shares issued (in shares)		9,926
Consideration received on transaction		$ 9,900,000
Securities Purchase Agreement \| Series A Preferred Stock \| Wipro
Related Party Transaction [Line Items]
Number of shares issued (in shares)	9,926
Shares issuable upon conversion (in shares)	1,001,614
Shares issuable upon conversion (as percent)	16.00%
Consideration received on transaction	$ 9,900,000