Net Income per Limited Partnership Unit - Schedule of Reconciliation of Net Income and Allocation of Net Income to Limited Partners' Interest for Purposes of Computing Net Income per Limited Partner Unit (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Quarterly dividend distributions paid (in dollars per unit)	$ 0.5125	$ 0.2948