Related Party Transactions (Related Party Costs and Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Related party cost and expense:
Related party expenses, total	$ 16,567	$ 16,441
Sac Holdings [Member]
Related party cost and expense:
U-Haul lease expenses	681	688
U-Haul commission expenses	14,926	14,701
Private Mini [Member]
Related party cost and expense:
U-Haul commission expenses	$ 960	$ 1,052

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

+ Details

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- Definition

Amount of general and administrative expense classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Details

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