Equity - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended					12 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) class vote $ / shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($) $ / shares
Class of Stock [Line Items]
Number of common stock classes outstanding | class						2
Distributions in excess of required tax distributions to members | $						$ 34,368	$ 47,368	$ 50,649
Excess Distribution of Required Tax Distributions
Class of Stock [Line Items]
Distributions in excess of required tax distributions to members | $						$ 34,167	$ 34,014	$ 30,698
Common Class A
Class of Stock [Line Items]
Number of votes per share of common stock | vote						1
Common Class B
Class of Stock [Line Items]
Number of votes per share of common stock | vote						10
March 2021 Offering | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)	1,453,110
Shares issued in connection with registered offering (in USD per share) | $ / shares	$ 87.36					$ 87.36
Proceeds from offering | $	$ 118,710
March 2021 Offering, Current Stockholder Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)	94,245
March 2021 Offering, New Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)	1,358,865
September 2020 Offering | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)		2,207,380,000
Shares issued in connection with registered offering (in USD per share) | $ / shares		$ 70.18
Proceeds from offering | $		$ 149,650
September 2020 Offering, Current Stockholder Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)		75,000
September 2020 Offering, New Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)		2,132,380,000
June 2020 Offering | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)			2,995,757
Shares issued in connection with registered offering (in USD per share) | $ / shares			$ 70.09
Proceeds from offering | $			$ 204,979
June 2020 Offering, Current Stockholder Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)			71,242
June 2020 Offering, New Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)			2,924,515
September 2019 Offering | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)				2,680,089
Shares issued in connection with registered offering (in USD per share) | $ / shares				$ 60.01
Proceeds from offering | $				$ 147,122
September 2019 Offering, Current Stockholder Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)				228,456
September 2019 Offering, New Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)				2,451,633
March 2019 Offering | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)					1,449,303
Shares issued in connection with registered offering (in USD per share) | $ / shares					$ 45.65			$ 45.65
Proceeds from offering | $					$ 63,878
March 2019 Offering, Current Stockholder Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)					50,000
March 2019 Offering, New Issuance | Common Class A
Class of Stock [Line Items]
Shares issued in connection with offering (in shares)					1,399,303
Member Units [Member] | Common Class B
Class of Stock [Line Items]
Purchase of interest by parent (in shares)	1,101,365	1,936,880	2,271,636	1,466,712	711,943
Member Units [Member] | Common Class C
Class of Stock [Line Items]
Purchase of interest by parent (in shares)	257,500	195,500,000	652,879	984,921	687,360