Related Party Transactions (Related Party Revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Related party transactions:
Management fees revenue	$ 29,075	$ 26,533	$ 25,341
Revenue from related parties	33,955	32,619	36,173
Sac Holdings [Member]
Related party transactions:
Interest income revenue	4,880	4,960	5,914
Management fees revenue	19,635	18,657	18,472
Private Mini [Member]
Related party transactions:
Interest income revenue		1,126	4,918
Management fees revenue	3,495	3,330	2,614
Mercury [Member]
Related party transactions:
Management fees revenue	$ 5,945	$ 4,546	$ 4,255

No definition available.

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- Definition

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=63488584&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=63488584&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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