Related Party Transactions (Related Party Costs and Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Related party cost and expense:
Related party expenses, total	$ 18,757	$ 14,798	$ 55,937	$ 51,933
Blackwater [Member]
Related party cost and expense:
U-Haul lease expenses	658	658	1,973	1,974
U-Haul commission expenses	$ 18,099	$ 14,140	$ 53,964	$ 49,959

No definition available.

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- Definition

Costs of sales and operating expenses for the period incurred from transactions with related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121573735&loc=d3e41499-112717

+ Details

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- Definition

Amount of general and administrative expense classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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