Subsequent Events - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Aug. 01, 2014 Subsequent Events [Member]
Subsequent Event [Line Items]
Date of announcement of dividend					Aug. 01, 2014
Dividends declared per share (in dollars per share)	$ 0.11	$ 0.11	$ 0.22	$ 0.22	$ 0.11
Date of payment of dividend					Aug. 29, 2014
Date of record of dividend					Aug. 15, 2014