Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 83,860	$ 73,484	$ 169,661	$ 143,447
Subscription and support
Disaggregation of Revenue [Line Items]
Total revenue	70,696	60,472	139,057	116,595
XBRL professional services
Disaggregation of Revenue [Line Items]
Total revenue	8,313	9,522	21,745	20,932
Other services
Disaggregation of Revenue [Line Items]
Total revenue	4,851	3,490	8,859	5,920
Information technology
Disaggregation of Revenue [Line Items]
Total revenue	11,191	10,001	22,281	19,163
Diversified financials
Disaggregation of Revenue [Line Items]
Total revenue	10,700	8,263	20,567	15,701
Consumer discretionary
Disaggregation of Revenue [Line Items]
Total revenue	9,312	8,329	18,749	16,308
Industrials
Disaggregation of Revenue [Line Items]
Total revenue	9,179	8,212	18,403	16,004
Banks
Disaggregation of Revenue [Line Items]
Total revenue	8,454	6,945	16,955	13,623
Healthcare
Disaggregation of Revenue [Line Items]
Total revenue	8,325	6,930	16,745	13,514
Energy
Disaggregation of Revenue [Line Items]
Total revenue	5,557	5,446	11,981	11,090
Other
Disaggregation of Revenue [Line Items]
Total revenue	$ 21,142	$ 19,358	$ 43,980	$ 38,044