Investments - Additional Information (Detail) (USD $)	1 Months Ended		9 Months Ended
	Jul. 31, 2014	May 31, 2014	Sep. 30, 2014 Collateralized_Loan_Obligations	Dec. 31, 2013
Investment [Line Items]
Percentage of management fee revenue allocated to Carlyle			55.00%
Percentage of carried interest income to be allocated to Partnership for future interests in future carry funds			7.50%
Additional investment in partnership			$ 7,500,000
Additional investment percentage			7.50%
Percentage of carried interest to be received if certain options to purchase additional interests are made	40.00%	40.00%
Number of years until Carlyle can purchase the remaining interests in NGP Management			13 years
Partnership vested period			5 years
Consideration amount upon the termination of the investment period of the NGP X Fund			7,500,000
Partnership's basis difference based on underlying net assets			156,100,000	199,600,000
Basis difference amortization period			10 years
Exercise price for option to acquire additional interests in the general partners of all future carry funds advised by NGP	61,300,000	35,200,000
Additional amount paid on acquisition of general partner investment in NGP Fund X	16,600,000
Carrying value of investment in NGP X general partner attributable to the carried interest allocation			60,800,000
Carrying value of general partner investments in NGP X fund			23,100,000
Trading securities			13,200,000	14,200,000
Number of collateralized loan obligations			6
Total assets of the CLOs that were formed during the year			4,300,000,000
Minimum percent of aggregate assets for individual investments with fair value			5.00%
Corporate Mezzanine Securities and Bonds [Member]
Investment [Line Items]
Trading securities			13,200,000	14,200,000
Barclays Natural Resource Investments [Member]
Investment [Line Items]
Contingent consideration			183,000,000.0
Accrued contingent consideration obligation			153,000,000
Carlyle Holdings [Member]
Investment [Line Items]
Issuance of partnership units			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. [Member]
Investment [Line Items]
Contingent consideration			45,000,000.0
ECM Capital, L.P. [Member] | Barclays Natural Resource Investments [Member]
Investment [Line Items]
Purchase price			$ 384,000,000
Issuance of partnership units			996,572
ECM Capital, L.P. [Member] | Barclays Natural Resource Investments [Member] | Option Exercisable between July 1, 2014 and July 1, 2015 [Member]
Investment [Line Items]
Percentage of carried interest to be received if certain options to purchase additional interests are made			40.00%
ECM Capital, L.P. [Member] | Barclays Natural Resource Investments [Member] | Option Exercisable from December 20, 2012 until January 1, 2015 [Member]
Investment [Line Items]
Percentage of carried interest to be received if certain options to purchase additional interests are made			40.00%
Management Fee-Related Revenues [Member]
Investment [Line Items]
Percentage of management fee revenue allocated to Carlyle			47.50%