Revenue Recognition - Schedule of Revenues Disaggregated by Service Line (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Total services	$ 157,743,000	$ 136,028,000	$ 310,363,000	$ 265,628,000
Patient Management Services [Member]
Disaggregation Of Revenue [Line Items]
Total services	104,669,000	90,250,000	205,118,000	175,471,000
Network Solutions Services [Member]
Disaggregation Of Revenue [Line Items]
Total services	$ 53,074,000	$ 45,778,000	$ 105,245,000	$ 90,157,000