Investments - Apollo's Investments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Schedule Of Investments [Abstract]
Investments, at Fair Value	$ 1,736,703	$ 1,744,412
Other investments	397,358	393,684
Total Investments	$ 2,134,061	$ 2,138,096