EQUITY COMPENSATION (Tables)

9 Months Ended

Sep. 30, 2019

Share-based Payment Arrangement [Abstract]

Schedule of equity-based compensation expense, net of assumed forfeitures

Equity-based compensation expense, net of forfeitures is included in the following table:

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2019		2018		2019		2018
Restricted units	$	21,430	$	19,251	$	66,226	$	55,798
Restricted units with a market condition	911		614		2,702		614
Options	52		3,660		4,310		9,953
Phantom shares	—		415		736		1,169
Equity-based compensation expense	$	22,393	$	23,940	$	73,974	$	67,534

Summary of unvested restricted units' activity

The following table presents unvested restricted units' activity during the nine months ended September 30, 2019:

	Restricted Units		Weighted Average Grant Date Fair Value Per Unit
Balance - January 1, 2019	16,255,475		$	19.21
Granted	4,202,622		20.61
Vested	(3,579,050	)	17.95
Forfeited	(234,035	)	19.33
Balance - September 30, 2019	16,645,012		$	19.83

The following table presents the unvested market condition awards' activity during the nine months ended September 30, 2019:

	Market Condition Awards Units	Weighted Average Grant Date Fair Value Per Unit
Balance - January 1, 2019	1,333,334	$	9.30
Granted	—	—
Vested	—	—
Forfeited	—	—
Balance - September 30, 2019	1,333,334	$	9.30

Summary of unvested options activity

A summary of options activity during the nine months ended September 30, 2019 is presented below:

	Options		Weighted Average Exercise Price		Weighted Average Remaining Life (in years)	Aggregate Intrinsic Value
Balance - January 1, 2019	18,741,504		$	18.99	4.88	$	—
Exercised	(4,515,448	)	19.00		—	—
Expired	(366,366	)	19.00		—	—
Forfeited	(42,270	)	19.00		—	—
Balance - September 30, 2019	13,817,420		$	18.99	4.50	$	108,079
Exercisable at September 30, 2019	13,707,603		$	18.99	4.49	$	107,167

Summary of unvested phantom units activity

A summary of unvested phantom shares' activity during the nine months ended September 30, 2019 is presented below:

	Phantom Shares		Weighted Average Grant Date Fair Value Per Share
Balance - January 1, 2019	66,287		$	19.00
Vested	(61,502	)	19.00
Forfeited	(4,785	)	19.00
Balance - September 30, 2019	—		$	—