Equity Plans (Tables)

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award

The following table summarizes information regarding restricted and phantom unit activity during the years ended December 31, 2016 and 2015.

	Units			Weighted-Average Grant Date Fair Value
Unvested - January 1, 2015		131,588		$	132.10
Vested - restricted units		(91,798	)	$	121.13
Vested - phantom units		(4,856	)	$	67.10
Granted - restricted units		142,255		$	55.25
Granted - phantom units		42,349		$	62.31
Modification - restricted units		226,401		$	68.85
Modification - phantom units		41,269		$	58.36
Forfeited(1)		(20,994	)	$	89.97
Unvested - December 31, 2015		466,214		$	69.80
Vested - restricted units		(193,295	)	$	76.82
Granted - restricted units		1,067,535		$	14.58
Granted - phantom units		17,467		$	15.54
Forfeited		(65,591	)	$	25.13
Unvested - December 31, 2016		1,292,330		$	24.67

The following table summarizes information regarding restricted and phantom unit activity during the year ended December 31, 2015:

	Units			Weighted-Average Grant Date Fair Value
Unvested - January 1, 2015		834,796		$	23.18
Vested - restricted units		(457,458	)	$	22.91
Vested - phantom units		(21,578	)	$	16.05
Granted - restricted units		535,858		$	15.89
Granted - phantom units		171,648		$	15.76
Modification - restricted units		(823,277	)	$	20.06
Modification - phantom units		(150,070	)	$	18.93
Forfeited(1)		(89,919	)	$	16.05
Unvested - December 31, 2015		—		$	—