Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2022	Mar. 31, 2022
Statement Of Financial Position [Abstract]
Finance receivables, allowance for credit losses	$ 1,484	$ 1,246
Common Stock, Par or Stated Value Per Share
Common Stock, Shares Authorized	100,000	100,000
Common Stock, Shares, Issued	91,500	91,500
Common Stock, Shares, Outstanding	91,500	91,500