EQUITY COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of the grant date fair value associated with each equity award issued as well as the expense recognized

The following summarizes the grant date fair value associated with each equity award issued prior to the Company's IPO that occurred on May 1, 2014, as well as the expense recognized related to these awards for the year ended December 31, 2014:

			Compensation Expense, Net of Forfeitures			Unrecognized Compensation Expenses(1)
	Grant Date Fair Value		For the Year Ended December 31, 2014			As of April 30, 2014
AEP I Profit Interest	$	38,400	$	—		$	—
AEP II Profit Interests	33,423		14,714			12,709
AEP IV Profit Interests	10,657		10,657			10,657
AEP VI Profit Interests	9,047		9,047			9,047
Exchanged AEP Awards	68,607		—			—
Indicus:
Membership Interest	20,700		11,913			10,532
Profit Interest	5,464		(3,871		)	—
AREA Membership Interest	25,381		20,678			17,555
Total	$	211,679	$	63,138		$	60,500

(1) On May 1, 2014, the unrecognized compensation expenses associated with awards granted prior to the IPO were recognized as the vesting of these awards was accelerated. These amounts are included in the compensation expenses presented above.

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 Year Ended December 31,				Period from May 1, 2014 through December 31, 2014
	2016		2015
Restricted units	$	21,894	$	14,035	$	8,826
Options	15,450		16,575		9,869
Phantom units	1,721		1,634		1,396
Equity-based compensation expense	$	39,065	$	32,244	$	20,091

Summary of unvested restricted units' activity

The following table presents unvested restricted units’ activity during the year ended December 31, 2016:

	Restricted Units		Weighted Average Grant Date Fair Value Per Unit
Balance - January 1, 2016	4,657,761		$	18.01
Granted	3,988,873		14.58
Vested	(47,729	)	17.32
Forfeited	(540,533	)	16.95
Balance - December 31, 2016	8,058,372		$	16.38

Summary of unvested options activity

A summary of unvested options activity during the year ended December 31, 2016 is presented below:

	Options		Weighted Average Exercise Price		Weighted Average Remaining Life (in years)	Aggregate Intrinsic Value
Balance - January 1, 2016	24,082,415		$	18.99	8.34
Granted	—		—		—
Vested	(153,449	)	19.00		7.29
Forfeited	(1,827,027	)	19.00		—
December 31, 2016	22,101,939		$	18.99	7.35	$	4,586
Exercisable at December 31, 2016	130,200		$	19.00	7.29	$	26

Schedule of weighted average assumptions used for fair value

The fair value of each option granted during each year is measured on the date of the grant using the Black‑Scholes option pricing model and the following weighted average assumptions:

	For the Year Ended December 31,		Period from May 1, 2014 through December 31, 2014
	2016(2)	2015
Risk-free interest rate	N/A	1.71% to 1.80%	2.06% to 2.22%
Weighted average expected dividend yield	N/A	5.00%	5.00%
Expected volatility factor(1)	N/A	35.00% to 36.00%	34.00% to 35.00%
Expected life in years	N/A	6.66 to 7.49	6.92 to 7.00

(1)   Expected volatility is based on comparable companies using daily stock prices.

(2) There were no new options granted during the year ended December 31, 2016.

Summary of unvested Phantom units activity

A summary of unvested phantom units’ activity during the year ended December 31, 2016 is presented below:

	Phantom Units		Weighted Average Grant Date Fair Value Per Unit		Phantom Units	Weighted Average Grant Date Fair Value Per Unit
Balance - January 1	418,115		$	19.00	610,711	$	19.00
Vested	(98,733	)	19.00		(116,802)	19.00
Forfeited	(53,244	)	19.00		(75,794)	19.00
Balance - December 31	266,138		$	19.00	418,115	$	19.00

Schedule of Adoption of ASU 2016-09

The Company adopted ASU 2016-09 effective January 1, 2016 using a modified retrospective approach and recorded a cumulative-effect adjustment with the following impact to beginning equity:

	Partners' Capital			Non-Controlling Interest in AOG Entities			Redeemable Interest in AOG Entities
Balance at December 31, 2015	$	251,537		$	397,883		$	23,505
Retained earnings	(3,357		)	(5,470		)	(38		)
Paid-in-capital - equity compensation	3,767			6,138			43
Distributions - dividend equivalent	(410		)	(668		)	(5		)
Balance at December 31, 2015 (as adjusted)	$	251,537		$	397,883		$	23,505