Quarterly report pursuant to Section 13 or 15(d)

Subsequent Events - Additional Information (Detail)

v2.4.0.6
Subsequent Events - Additional Information (Detail) (USD $)
3 Months Ended 1 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Apr. 29, 2013
Subsequent Event [Member]
Dividend declared per common share $ 0.30 $ 0.30 $ 0.30
Dividend declaration date Feb. 19, 2013   Apr. 29, 2013
Dividend payment date Mar. 19, 2013   May 28, 2013
Dividend date of record     May 14, 2013