Related Party Transactions (Related Party Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Related party transactions:
Management fees revenue	$ 6,320	$ 5,796	$ 12,431	$ 11,473
Revenue from related parties	7,569	8,855	16,045	17,562
Sac Holdings [Member]
Related party transactions:
Interest income revenue	1,249	1,719	2,488	3,423
Management fees revenue	$ 4,883	4,622	9,697	9,145
Private Mini [Member]
Related party transactions:
Interest income revenue		1,340	1,126	2,666
Management fees revenue	$ 878	648	1,624	1,284
Mercury [Member]
Related party transactions:
Management fees revenue	$ 559	$ 526	$ 1,110	$ 1,044

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- Definition

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

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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.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.1(c))

-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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