Commitments And Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2003	May 31, 2012	May 31, 2011	May 31, 2012	May 31, 2011
Commitments and Contingencies Disclosure [Line Items]
Land lease term	51 years
Prepaid land lease rent	$ 28.0
Prepaid land lease adjustments term	10 years
Rental expense		3.4	3.6	7.2	6.8
Lease expiration date				2019-05
Long-term income tax liabilities		$ 24.2		$ 24.2