Quarterly report pursuant to Section 13 or 15(d)

Dividends - Additional Information (Detail)

v2.4.0.6
Dividends - Additional Information (Detail) (USD $)
3 Months Ended 1 Months Ended
Mar. 31, 2013
Mar. 31, 2012
May 07, 2013
Subsequent Event
Dividends Payable [Line Items]      
Paid cash dividends, per share $ 0.08 $ 0.08  
Dividends declared per common share $ 0.08 $ 0.08 $ 0.09
Dividend payable, date declared, day month and year     May 07, 2013
Dividends payable, date to be paid, day, month and year     Jun. 04, 2013
Dividends payable, date of record, day, month and year     May 24, 2013