Related Party Revenue (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Related party transactions:
Management fees revenue	$ 25,341us-gaap_ManagementFeesRevenue	$ 24,493us-gaap_ManagementFeesRevenue	$ 24,378us-gaap_ManagementFeesRevenue
Revenue from related parties	36,173	36,912	38,134
Sac Holdings [Member]
Related party transactions:
Interest income revenue	5,914	7,071	8,373
Management fees revenue	18,472	18,007	18,731
Private Mini [Member]
Related party transactions:
Interest income revenue	4,918	5,348	5,383
Management fees revenue	2,614	2,437	2,305
Mercury [Member]
Related party transactions:
Management fees revenue	$ 4,255	$ 4,049	$ 3,342

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

+ 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 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Definition

Revenue, comprised of base and incentive revenue derived from the management of joint ventures, managing third-party properties, or another entity's operations.

+ 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 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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