Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Restricted Cash and Cash Equivalents - Additional Information (Detail)

v2.4.0.6
Restricted Cash and Cash Equivalents - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Mar. 31, 2012
Restricted Cash and Cash Equivalents Items [Line Items]    
Restricted cash and cash equivalents related to insurance policy $ 5.0 $ 5.2
Restricted cash and cash equivalents related to early contribution to AICF   $ 138.7