Borrowings - SBI Bonds (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 JPY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 JPY (¥)	Jul. 25, 2016 USD ($)	Jul. 25, 2016 JPY (¥)
Debt Instrument [Line Items]
Outstanding principal amount	$ 1,766,755,000		$ 1,766,755,000			$ 1,751,816,000
SBI bonds
Debt Instrument [Line Items]
Outstanding principal amount	21,755,000		21,755,000			24,816,000
VFH | SBI bonds | SBI Bonds
Debt Instrument [Line Items]
Face amount								$ 33,100,000	¥ 3,500,000,000
Outstanding principal amount	21,800,000		21,800,000		¥ 3,500,000,000	$ 24,800,000	¥ 3,500,000,000
Gain (loss) on due to change in currency rates	$ 1,400,000	$ 2,100,000	$ 3,100,000	$ 2,400,000