Fair Value - Quantitative Inputs and Assumptions used for Financial Assets and Liabilities Categories (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified					3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended				12 Months Ended	3 Months Ended										12 Months Ended														3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2013 Debt of Consolidated VIEs	Dec. 31, 2013 Subordinated Notes	Mar. 31, 2014 Subordinated Notes Discounted Cash Flows	Dec. 31, 2013 Subordinated Notes Discounted Cash Flows	Mar. 31, 2014 Subordinated Notes Minimum	Dec. 31, 2013 Subordinated Notes Minimum	Mar. 31, 2014 Subordinated Notes Maximum	Dec. 31, 2013 Subordinated Notes Maximum	Mar. 31, 2014 Subordinated Notes Weighted Average Discounted Cash Flows	Dec. 31, 2013 Subordinated Notes Weighted Average Discounted Cash Flows	Dec. 31, 2013 Senior Secured Notes	Mar. 31, 2014 Senior Secured Notes Discounted Cash Flows	Dec. 31, 2013 Senior Secured Notes Discounted Cash Flows	Mar. 31, 2014 Senior Secured Notes Minimum	Dec. 31, 2013 Senior Secured Notes Minimum	Mar. 31, 2014 Senior Secured Notes Maximum	Dec. 31, 2013 Senior Secured Notes Maximum	Mar. 31, 2014 Senior Secured Notes Weighted Average Discounted Cash Flows	Dec. 31, 2013 Senior Secured Notes Weighted Average Discounted Cash Flows	Dec. 31, 2013 Corporate Notes And Loans		Dec. 31, 2013 Contingent Consideration Obligations	Dec. 31, 2013 Contingent Consideration Obligations Discounted Cash Flows	Mar. 31, 2014 Contingent Consideration Obligations Minimum Discounted Cash Flows	Mar. 31, 2014 Contingent Consideration Obligations Maximum Discounted Cash Flows	Mar. 31, 2014 Contingent Consideration Obligations Weighted Average Discounted Cash Flows	Dec. 31, 2013 AAA Investments		Dec. 31, 2013 Investments Fair Value Held By Senior Loan Fund		Dec. 31, 2013 Investments In HFA And Other		Dec. 31, 2013 Athene And AAA Derivative	Dec. 31, 2013 Athene And AAA Derivative Discounted Cash Flows	Mar. 31, 2014 Athene And AAA Derivative Discounted Cash Flows	Mar. 31, 2014 Athene And AAA Derivative Weighted Average Discounted Cash Flows	Mar. 31, 2014 Consolidated Variable Interest Entities	Dec. 31, 2013 Consolidated Variable Interest Entities	Mar. 31, 2014 Consolidated Variable Interest Entities Debt of Consolidated VIEs	Mar. 31, 2014 Consolidated Variable Interest Entities Subordinated Notes	Mar. 31, 2014 Consolidated Variable Interest Entities Senior Secured Notes	Mar. 31, 2014 Consolidated Variable Interest Entities Corporate Notes And Loans		Mar. 31, 2014 Consolidated Variable Interest Entities Bank Debt Term Loans	Dec. 31, 2013 Consolidated Variable Interest Entities Bank Debt Term Loans	Mar. 31, 2014 Consolidated Variable Interest Entities Stock	Dec. 31, 2013 Consolidated Variable Interest Entities Stock	Mar. 31, 2014 Consolidated Variable Interest Entities Stock Minimum Market Comparable Companies	Dec. 31, 2013 Consolidated Variable Interest Entities Stock Minimum Market Comparable Companies	Mar. 31, 2014 Consolidated Variable Interest Entities Stock Maximum Market Comparable Companies	Dec. 31, 2013 Consolidated Variable Interest Entities Stock Maximum Market Comparable Companies	Mar. 31, 2014 Consolidated Variable Interest Entities Stock Weighted Average Market Comparable Companies	Dec. 31, 2013 Consolidated Variable Interest Entities Stock Weighted Average Market Comparable Companies	Mar. 31, 2014 Consolidated Variable Interest Entities Corporate Loans/Bonds		Dec. 31, 2013 Consolidated Variable Interest Entities Corporate Loans/Bonds		Mar. 31, 2014 Fair Value, Measurements, Recurring	Dec. 31, 2013 Fair Value, Measurements, Recurring	Mar. 31, 2014 Fair Value, Measurements, Recurring Contingent Consideration Obligations		Dec. 31, 2013 Fair Value, Measurements, Recurring Contingent Consideration Obligations		Mar. 31, 2014 Fair Value, Measurements, Recurring AAA Investments		Dec. 31, 2013 Fair Value, Measurements, Recurring AAA Investments		Mar. 31, 2014 Fair Value, Measurements, Recurring Investments Fair Value Held By Senior Loan Fund		Dec. 31, 2013 Fair Value, Measurements, Recurring Investments Fair Value Held By Senior Loan Fund		Mar. 31, 2014 Fair Value, Measurements, Recurring Investments In HFA And Other		Dec. 31, 2013 Fair Value, Measurements, Recurring Investments In HFA And Other		Mar. 31, 2014 Fair Value, Measurements, Recurring Athene And AAA Derivative		Dec. 31, 2013 Fair Value, Measurements, Recurring Athene And AAA Derivative		Mar. 31, 2014 Level III Fair Value, Measurements, Recurring	Dec. 31, 2013 Level III Fair Value, Measurements, Recurring	Mar. 31, 2014 Level III Fair Value, Measurements, Recurring Contingent Consideration Obligations	Dec. 31, 2013 Level III Fair Value, Measurements, Recurring Contingent Consideration Obligations		Mar. 31, 2014 Level III Fair Value, Measurements, Recurring AAA Investments		Dec. 31, 2013 Level III Fair Value, Measurements, Recurring AAA Investments		Dec. 31, 2013 Level III Fair Value, Measurements, Recurring Investments Fair Value Held By Senior Loan Fund		Mar. 31, 2014 Level III Fair Value, Measurements, Recurring Investments In HFA And Other		Dec. 31, 2013 Level III Fair Value, Measurements, Recurring Investments In HFA And Other		Mar. 31, 2014 Level III Fair Value, Measurements, Recurring Athene And AAA Derivative		Dec. 31, 2013 Level III Fair Value, Measurements, Recurring Athene And AAA Derivative		Apr. 04, 2014 Athene Holding Ltd. Subsequent Event
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Sale of stock, price per share																																					$ 26.00	$ 26.00																																																															$ 26
Investments, at fair value																																							$ 14,254,534	$ 14,126,362																										$ 2,147,415	[1]	$ 1,942,051	[1]	$ 29,909	[1]	$ 29,603	[1]	$ 59,324	[1]	$ 40,373	[1]										$ 2,147,415	[1]	$ 1,942,051	[1]	$ 892	[1]	$ 59,324	[1]	$ 40,373	[1]
Derivative asset, at fair value																																																																														206,476	[2]	130,709	[2]																206,476	[2]	130,709	[2]
Assets, fair value	4,250,666	4,033,562																											1,942,051	[3]	892	[4]	40,373	[4]	130,709				1,837,451	1,919,537						60,760	18,467	6,103	7,938							1,748,318	[4]	1,893,132	[4]	16,697,658	16,269,098																					4,250,666	4,033,562
Financial liabilities, fair value	10,548,793	10,129,658	9,994,147	835,149									2,132,576									7,026,422	[4]	135,511																	10,422,320	835,484	2,148,989	7,437,847	[4]															12,654,728	12,559,473																					10,548,793	10,129,658
Fair Value Inputs, Probability of Default							1.00%	1.00%	1.50%	1.50%	1.30%	1.30%		2.00%	2.00%					2.00%
Contingent consideration obligations																																																														$ 126,473	[5]	$ 135,511	[5]																			$ 126,473	$ 135,511	[5]
Discount rate							10.00%	10.00%	12.00%	12.00%	11.10%	10.80%				1.90%	1.90%	2.20%	2.20%	1.80%	2.00%				15.30%	10.50%	18.50%	15.40%								15.00%
Implied multiple																																				1.1
Comparable multiple																																																		6.5	6.0	11.2	9.5	8.0	7.9
Recovery rate					75.00%	75.00%					75.00%					30.00%	30.00%	70.00%	70.00%	65.00%	65.20%

[1] 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.

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

[3] 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

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

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