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Certain Relationships and Related Party Transactions (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
	Jan. 30, 2018	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Snap Kitchen
Related Party Transaction [Line Items]
Ownership percentage		7.00%			7.00%
Securities Purchase Agreement \| Series A Preferred Stock
Related Party Transaction [Line Items]
Number of shares issued (in shares)	9,926
Consideration received on transaction	$ 9.9
Wipro
Related Party Transaction [Line Items]
Capitalized costs for internally developed software services received		$ 0.0			$ 1.7
Accounts payable, related parties		1.4			1.4		$ 5.0
Wipro \| Agency Related Services
Related Party Transaction [Line Items]
Revenue from related parties		0.7
Wipro \| Technology Related Services
Related Party Transaction [Line Items]
Expenses from transactions with related party		$ 2.6		$ 3.2	$ 9.5	$ 9.3
One-time termination charge			$ 2.1
Annual savings			$ 3.3
Wipro \| Securities Purchase Agreement \| Series A Preferred Stock
Related Party Transaction [Line Items]
Number of shares issued (in shares)	9,926.000
Shares issuable upon conversion (in shares)	1,001,614.000
Shares issuable upon conversion (as percent)	16.00%
Consideration received on transaction	$ 9.9