(15) Equity-Based Awards

The following table summarizes information regarding phantom unit awards (the “Affiliate Grants”) to employees of the Provider who provide services to the Partnership under the LTIP:


	Time-Based			Performance-Based			Total Affiliate Grant
	Phantom Units			Phantom Units			Phantom Units
		Weighted-			Weighted-			Weighted-
		Average			Average			Average
		Grant Date			Grant Date			Grant Date
		Fair Value			Fair Value			Fair Value
	Units	(per unit)(1)		Units	(per unit)(1)		Units	(per unit)(1)
Nonvested December 31, 2017	595,866	$	22.32	111,104	$	25.52	706,970	$	22.82
Granted	243,442	$	28.65	116,401	$	28.65	359,843	$	28.65
Forfeitures	(16,123)	$	23.76	—	$	—	(16,123)	$	23.76
Vested	—	$	—	—	$	—	—	$	—
Nonvested March 31, 2018	823,185	$	24.16	227,505	$	27.12	1,050,690	$	24.80

(1)

Determined by dividing the aggregate grant date fair value of awards by the number of awards issued.

139,810 of performance-based phantom unit awards under the LTIP vested on December 31, 2017. Upon settlement of the associated units on January 31, 2018, the Partnership paid $2.3 million to the General Partner who then acquired 81,708 common units at a market price of $28.65 per unit from a wholly owned subsidiary of the sponsor to satisfy its obligations under the LTIP. The Partnership also paid $1.7 million to the Provider to satisfy the tax-withholding requirements associated with such units. The Provider recognized an additional $0.1 million in expense for the change in fair value of these awards between the vesting and settlement dates of such awards, which was allocated to the Partnership in the same manner as other corporate expenses.

The following table summarizes information regarding phantom unit awards to certain non-employee directors of the General Partner (the “Director Grants”) under the LTIP:


	Time-Based			Performance-Based			Total Director Grant
	Phantom Units			Phantom Units			Phantom Units
		Weighted-			Weighted-			Weighted-
		Average			Average			Average
		Grant Date			Grant Date			Grant Date
		Fair Value			Fair Value			Fair Value
	Units	(per unit)(1)		Units	(per unit)(1)		Units	(per unit)(1)
Nonvested December 31, 2017	15,840	$	25.25	—	$	—	15,840	$	25.25
Granted	13,964	$	28.65	—	$	—	13,964	$	28.65
Forfeitures	—	$	—	—	$	—	—	$	—
Vested	(15,840)	$	25.25	—	$	—	(15,840)	$	25.25
Nonvested March 31, 2018	13,964	$	28.65	—	$	—	13,964	$	28.65

(1)

Determined by dividing the aggregate grant date fair value of awards by the number of awards issued.

In February 2018, Director Grants valued at $0.4 million were granted and vest on the first anniversary of the grant date. In February 2018, the Director Grants that were nonvested at December 31, 2017 vested and common units were issued.

The distribution equivalent rights (“DERs”) associated with the Affiliate Grants and the Director Grants subject to time-based vesting entitle the recipients to receive payments equal to any distributions made by the Partnership to the holders of common units within 60 days following the record date for such distributions. The DERs associated with the Affiliate Grants subject to performance-based vesting will remain outstanding and unpaid from the grant date until the earlier of the settlement or forfeiture of the related performance-based phantom units.

Unpaid DER amounts related to the performance-based Affiliate Grants at March 31, 2018 were $1.1 million, of which $0.7 million are included in related-party accrued liabilities and $0.4 million are included in other long-term liabilities on the consolidated balance sheets. Unpaid DER amounts related to the performance-based Affiliate Grants at December 31, 2017 were $0.9 million, of which $0.7 million are included in accrued liabilities and $0.2 million are included in other long-term liabilities. DER distributions related to the time-based Affiliate Grants were $0.5 million for the three months ended March 31, 2018 and are included in related-party accrued liabilities. DER distributions were insignificant for the three months ended March 31, 2017.