Real Estate and Lending Activities - Assets Acquired (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	$ 165,700	$ 115,000
Land [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	21,591	8,515
Building [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	88,409	99,602
Intangible lease assets - subject to amortization [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired		6,883
Net investments in direct financing leases [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	10,700
Other loans [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	5,000
Mortgage loans [Member]
Significant Acquisitions and Disposals [Line Items]
Total assets acquired	$ 40,000