Revenue from Contracts with Customers - Schedule of Revenues Disaggregated by Major Revenue Categories and by Occurrence (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Disaggregation Of Revenue [Line Items]
Total revenues	$ 136,382	$ 137,740	$ 134,256	$ 131,861	$ 134,785	$ 130,867	$ 130,321	$ 133,200	$ 540,239	$ 529,173	$ 531,019
Subscription Services
Disaggregation Of Revenue [Line Items]
Total revenues									127,602	117,502	106,325
Support And Maintenance
Disaggregation Of Revenue [Line Items]
Total revenues									158,619	160,798	163,805
Managed Services
Disaggregation Of Revenue [Line Items]
Total revenues									104,549	98,203	113,311
Electronic Data Interchange And Data Services
Disaggregation Of Revenue [Line Items]
Total revenues									98,543	97,418	92,773
Recurring Revenue
Disaggregation Of Revenue [Line Items]
Total revenues	124,490	124,787	120,589	119,447	120,151	117,446	116,317	120,007	489,313	473,921	476,214
Software License and Hardware
Disaggregation Of Revenue [Line Items]
Total revenues									27,270	35,122	34,017
Other Non-recurring Services
Disaggregation Of Revenue [Line Items]
Total revenues									23,656	20,130	20,788
Software Hardware and Other Non-recurring
Disaggregation Of Revenue [Line Items]
Total revenues	$ 11,892	$ 12,953	$ 13,667	$ 12,414	$ 14,634	$ 13,421	$ 14,004	$ 13,193	$ 50,926	$ 55,252	$ 54,805