Fair Value - Valuation of Financial Assets and Liabilities by the Fair Value Heirarchy (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	$ 4,250,666		$ 4,033,562
Liabilites, fair value	10,548,793		10,129,658
AAA Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			1,942,051	[1]
Investments Fair Value Held By Senior Loan Fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			892	[2]
Investments In HFA And Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			40,373	[2]
Athene And AAA Derivative
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			130,709
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	16,697,658		16,269,098
Liabilites, fair value	12,654,728		12,559,473
Fair Value, Measurements, Recurring | Consolidated Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	14,254,534	[3]	14,126,362	[3]
Debt, at fair value	12,528,255	[3]	12,423,962	[3]
Fair Value, Measurements, Recurring | AAA Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	2,147,415	[4]	1,942,051	[4]
Fair Value, Measurements, Recurring | Investments Fair Value Held By Senior Loan Fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	29,909	[4]	29,603	[4]
Fair Value, Measurements, Recurring | Investments In HFA And Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	59,324	[4]	40,373	[4]
Fair Value, Measurements, Recurring | Athene And AAA Derivative
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, at fair value	206,476	[5]	130,709	[5]
Fair Value, Measurements, Recurring | Level I
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	4,378	[6]	3,455	[6]
Fair Value, Measurements, Recurring | Level I | Consolidated Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	4,378	[3],[6]	3,455	[3],[6]
Fair Value, Measurements, Recurring | Level II
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	12,442,614	[6]	12,232,081	[6]
Liabilites, fair value	2,105,935	[6]	2,429,815	[6]
Fair Value, Measurements, Recurring | Level II | Consolidated Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	12,412,705	[3],[6]	12,203,370	[3],[6]
Debt, at fair value	2,105,935	[3],[6]	2,429,815	[3],[6]
Fair Value, Measurements, Recurring | Level II | Investments Fair Value Held By Senior Loan Fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	29,909	[4],[6]	28,711	[4],[6]
Fair Value, Measurements, Recurring | Level III
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	4,250,666		4,033,562
Liabilites, fair value	10,548,793		10,129,658
Fair Value, Measurements, Recurring | Level III | Consolidated Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	1,837,451	[3]	1,919,537	[3]
Debt, at fair value	10,422,320	[3]	9,994,147	[3]
Fair Value, Measurements, Recurring | Level III | AAA Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	2,147,415	[4]	1,942,051	[4]
Fair Value, Measurements, Recurring | Level III | Investments Fair Value Held By Senior Loan Fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value			892	[4]
Fair Value, Measurements, Recurring | Level III | Investments In HFA And Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value	59,324	[4]	40,373	[4]
Fair Value, Measurements, Recurring | Level III | Athene And AAA Derivative
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset, at fair value	206,476	[5]	130,709	[5]
Contingent Consideration Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilites, fair value			135,511
Contingent Consideration Obligations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration obligations	126,473	[7]	135,511	[7]
Contingent Consideration Obligations | Fair Value, Measurements, Recurring | Level III
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration obligations	$ 126,473		$ 135,511	[7]

[1] The following table summarizes a look-through of the Company’s Level III investments by valuation methodology of the underlying securities held by AAA Investments: As of December 31, 2013 % ofInvestmentof AAA InvestmentsApproximate values based on net asset value of the underlying funds, which are based on the funds underlying investments that are valued using the following: Discounted Cash Flow$1,950,010(3) 100%Total Investments1,950,010 100%Other net liabilities(4)(7,959) Total Net Assets$1,942,051

[2] These securities are valued primarily using broker quotes.

[3] See note 4 for further disclosure regarding VIEs.

[4] See note 3 for further disclosure regarding the investment in AAA Investments, investments held by Apollo Senior Loan Fund, and investments in HFA and Other.

[5] See note 13 for further disclosure regarding the Athene Services Derivative and the AAA Services Derivative.

[6] All level I and II investments and liabilities were valued using third party pricing.

[7] See note 14 for further disclosure regarding Contingent Consideration Obligations.