Subsequent Events - Additional Information (Detail) (Subsequent Event, Dividend Declared, USD $)	1 Months Ended
	May 28, 2013
Subsequent Event | Dividend Declared
Subsequent Event [Line Items]
Common Stock cash dividends, per share	$ 0.125
Common Stock cash dividends, to be paid date	Jun. 28, 2013
Common Stock cash dividends, date of record	Jun. 14, 2013