Revenue Recognition - Schedule of Revenues Disaggregated by Service Line (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Total services	$ 185,443,000	$ 179,386,000	$ 177,426,000	$ 176,307,000	$ 171,359,000	$ 164,508,000	$ 157,743,000	$ 152,620,000	$ 718,562,000	$ 646,230,000	$ 552,644,000
Patient Management Services [Member]
Disaggregation Of Revenue [Line Items]
Total services									478,751,000	424,050,000	368,853,000
Network Solutions Services [Member]
Disaggregation Of Revenue [Line Items]
Total services									$ 239,811,000	$ 222,180,000	$ 183,791,000