Related Party Transations (Table Text Block)	3 Months Ended	9 Months Ended
Dec. 31, 2021	Dec. 31, 2021
Related Party Revenue [Abstract]
Related Party Revenue	Quarter Ended December 31, 2021 2020 (Unaudited) (In thousands) U-Haul management fee revenue from Blackwater $ 6,972 $ 6,350 U-Haul management fee revenue from Mercury 2,679 2,415 $ 9,651 $ 8,765	Nine Months Ended December 31, 2021 2020 (Unaudited) (In thousands) U-Haul management fee revenue from Blackwater $ 21,580 $ 19,142 U-Haul management fee revenue from Mercury 5,267 4,810 $ 26,847 $ 23,952
Related Party costs and expenses	Quarter Ended December 31, 2021 2020 (Unaudited) (In thousands) U-Haul lease expenses to Blackwater $ 604 $ 658 U-Haul commission expenses to Blackwater 21,086 18,099 $ 21,690 $ 18,757	Nine Months Ended December 31, 2021 2020 (Unaudited) (In thousands) U-Haul lease expenses to Blackwater $ 1,841 $ 1,973 U-Haul commission expenses to Blackwater 70,502 53,964 $ 72,343 $ 55,937
Related party assets		December 31, March 31, 2021 2021 (Unaudited) (In thousands) U-Haul receivable from Blackwater $ 45,804 $ 27,116 U-Haul receivable from Mercury 9,845 9,632 Other (a) 582 (1,353) $ 56,231 $ 35,395 (a)

The Company has not provided financial or other support explicitly or implicitly during the period ended to any of these entities that it was not previously contractually required to provide. The carrying amount and the classification of assets and liabilities in the Company's balance sheet that related to the Company's variable interest in the Blackwater's entities are noted here, which approximate the maximum exposure to loss as a result of the Company's involvement with these entities.

No definition available.

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