Investments - Additional Information (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2015 USD ($) collateralized_loan_obligation shares	Dec. 31, 2014 USD ($)
Schedule of Equity Method Investments [Line Items]
Percentage of carried interest income to be allocated to Partnership for future interests in future carry funds	47.50%
Number of years until Carlyle can purchase the remaining interests in NGP Management	10 years
Carrying value of investment in NGP X general partner attributable to carried interest allocation	$ 0	$ 18,500,000
Carrying value of general partner investments in NGP X	$ 20,700,000	20,400,000
Partnership vested period (in years)	5 years
Length of term in years of promissory note to Barclays (in years)	6 years
Approximate amount of contingent consideration to be paid in cash to Barclays in 2016	33.33%
Approximate amount of contingent consideration to be issued in a promissory note to Barclays in 2016	66.66%
Basis spread of variable rate promissory note (as a percent)	2.50%
Aggregate commitments closed for NGP XI fund	$ 5,300,000,000
Partnership's basis difference based on underlying net assets	$ 99,100,000	141,600,000
Basis difference amortization period (in years)	10 years
Trading securities and other investments	$ 22,900,000	$ 12,900,000
Number of collateralized loan obligations | collateralized_loan_obligation	5
Total assets of the CLOs that were formed during the year	$ 3,200,000,000
Minimum percent of aggregate assets for individual investments with fair value	5.00%
Management fee-related revenues
Schedule of Equity Method Investments [Line Items]
Percentage of management fee revenue allocated to Carlyle	55.00%	47.50%
Barclays Natural Resource Investments
Schedule of Equity Method Investments [Line Items]
Contingent consideration	$ 183,000,000.0
Accrued contingent consideration obligation	$ 183,000,000
Carlyle Holdings
Schedule of Equity Method Investments [Line Items]
Issuance of partnership units (in shares) | shares	597,944
Value of additional partnership units to be issued upon the satisfaction of certain performance conditions	$ 15,000,000.0
ECM Capital, L.P.
Schedule of Equity Method Investments [Line Items]
Contingent consideration	$ 45,000,000.0
ECM Capital, L.P. | Barclays Natural Resource Investments
Schedule of Equity Method Investments [Line Items]
Percentage of carried interest to be received if certain options to purchase additional interests are made	40.00%
Purchase price	$ 504,600,000
Issuance of partnership units (in shares) | shares	996,572
Corporate mezzanine securities and bonds
Schedule of Equity Method Investments [Line Items]
Trading securities and other investments	$ 22,900,000	$ 12,900,000