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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Stock-based Compensation - Compensation Expense (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Jan. 01, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$ 5,104,000	$ 4,335,000
Share-based compensation expense capitalized as software development costs	0	0
Decrease in retained earnings	(128,605,000)		$ (146,617,000)
Election to Recognize Share-based Award Forfeitures As They Occur
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Decrease in retained earnings				$ 500,000
Adjustments \| ASU 2016-09
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense		100,000
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	349,000	444,000
Selling, general and administrative expenses
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	4,755,000	3,891,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	4,053,000	3,818,000
Performance-based stock options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	110,000	25,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based compensation expense	$ 941,000	$ 492,000