Investments - Apollo's Investments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Investments [Abstract]
Investments, at fair value	$ 2,236,648	$ 2,012,027
Other investments	404,028	381,856
Total Investments	$ 2,640,676	$ 2,393,883