Long-Term Incentive Plan Units (Roll-Forward Of Company's LTIP Units Outstanding) (Details) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Director LTIP Units exercised	0	0
Long-Term Incentive Plan Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
LTIP Units Outstanding, beginning of period	491,159	469,539
Granted	1,723	0
Director LTIP Units exercised	0	0
LTIP Units Outstanding, end of period	492,882	469,539
LTIP Units Vested and Outstanding	461,155	440,828
Manager [Member] | Long-Term Incentive Plan Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
LTIP Units Outstanding, beginning of period	375,000	375,000
Granted	0	0
Director LTIP Units exercised	0	0
LTIP Units Outstanding, end of period	375,000	375,000
LTIP Units Vested and Outstanding	375,000	375,000
Non-Manager [Member] | Long-Term Incentive Plan Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
LTIP Units Outstanding, beginning of period	116,159	94,539
Granted	1,723	0
Director LTIP Units exercised	0	0
LTIP Units Outstanding, end of period	117,882	94,539
LTIP Units Vested and Outstanding	86,155	65,828