Components Of Equity - Additional Information (Detail) (USD $)	0 Months Ended
	May 01, 2013	May 02, 2012
Class of Stock [Line Items]
Date of declaration of dividends	May 01, 2013	May 02, 2012
Dividend declared per share	$ 0.30	$ 0.28
Date of dividend payment	Jun. 17, 2013	Jun. 15, 2012
Dividends payable to shareholders date of record	Jun. 03, 2013	Jun. 01, 2012