EQUITY BASED COMPENSATION - Estimated Unrecognized Expense (Details) - USD ($) $ in Millions	Dec. 31, 2017	Nov. 30, 2016
Equity Incentive Plan Units
Equity Based Payments
Estimated unrecognized equity-based payment expense	$ 538.1
Equity Incentive Plan Units | 2018
Equity Based Payments
Estimated unrecognized equity-based payment expense	227.5
Equity Incentive Plan Units | 2019
Equity Based Payments
Estimated unrecognized equity-based payment expense	163.9
Equity Incentive Plan Units | 2020
Equity Based Payments
Estimated unrecognized equity-based payment expense	103.0
Equity Incentive Plan Units | 2021
Equity Based Payments
Estimated unrecognized equity-based payment expense	33.6
Equity Incentive Plan Units | 2022
Equity Based Payments
Estimated unrecognized equity-based payment expense	9.2
Equity Incentive Plan Units | 2023
Equity Based Payments
Estimated unrecognized equity-based payment expense	0.9
KKR Holdings Principal Awards
Equity Based Payments
Estimated unrecognized equity-based payment expense	358.4	$ 320.9
KKR Holdings Principal Awards | 2018
Equity Based Payments
Estimated unrecognized equity-based payment expense	101.5
KKR Holdings Principal Awards | 2019
Equity Based Payments
Estimated unrecognized equity-based payment expense	96.2
KKR Holdings Principal Awards | 2020
Equity Based Payments
Estimated unrecognized equity-based payment expense	88.1
KKR Holdings Principal Awards | 2021
Equity Based Payments
Estimated unrecognized equity-based payment expense	47.4
KKR Holdings Principal Awards | 2022
Equity Based Payments
Estimated unrecognized equity-based payment expense	$ 25.2