Distributions To Unitholders (Details)		3 Months Ended						12 Months Ended
	Feb. 09, 2017 shares	Dec. 31, 2016 $ / shares shares	Sep. 30, 2016 $ / shares	Jun. 30, 2016 $ / shares	Mar. 31, 2016 $ / shares	Dec. 31, 2015 $ / shares	Sep. 30, 2015 $ / shares	Dec. 31, 2015 shares
Paid-in-kind units distributed								843,989
Class A preferred units converted to common shares, conversion ratio		0.1
Common Units
Distribution paid per unit | $ / shares		$ 0.4310	$ 0.4246	$ 0.4183	$ 0.4121	$ 0.4060	$ 0.4000
Common Units | Subsequent Event
Aggregate distribution of units	208,594
Class B Preferred
Distribution paid per unit | $ / shares		$ 0.2258	$ 0.4500	$ 0.4500	$ 0.4500	$ 0.3815
Aggregate distribution of units		208,594