Share Based Payments (Summary Of Unvested Share Awards Issued To Executives And Employees) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Unvested Share Awards [Abstract]
Shares Issued (in shares)	693,854
Shares Vested (in shares)	477,898	360,918
Unearned Compensation	$ 1,528	$ 1,550
Issued 12-23-2014 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	258,899
Vesting Period	5 years
Shares Vested (in shares)	258,899	172,599
Unearned Compensation		$ 457
Original Year Of Issuance Date 2017 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	10,809
Vesting Period	2 years
Vesting Schedule (in hundredths)	50.00%
Shares Vested (in shares)	885
Unearned Compensation	$ 156
Restricted Share Awards [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	64,160
Shares Vested (in shares)	39,860	14,230
Unearned Compensation	$ 416	$ 505
Restricted Share Awards [Member] | Issued 12-23-2014 [Member]
Unvested Share Awards [Abstract]
Vesting Schedule (in hundredths)	33.00%
Restricted Share Awards [Member] | Original Year Of Issuance Date 2016 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	30,070
Vesting Period	2 years
Vesting Schedule (in hundredths)	50.00%
Shares Vested (in shares)	18,160	497
Unearned Compensation	$ 194	$ 348
Restricted Share Awards [Member] | Original Year Of Issuance Date 2015 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	23,281
Shares Vested (in shares)	20,815	13,733
Unearned Compensation	$ 66	$ 157
Minimum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2017 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	$ 18.51
Minimum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2016 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	18.02
Minimum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2015 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	$ 21.76
Vesting Period	2 years
Vesting Schedule (in hundredths)	25.00%
Maximum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2017 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	$ 18.53
Maximum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2016 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	21.11
Maximum [Member] | Restricted Share Awards [Member] | Original Year Of Issuance Date 2015 [Member]
Unvested Share Awards [Abstract]
Share Price on date of grant (in dollars per share)	$ 28.09
Vesting Period	4 years
Vesting Schedule (in hundredths)	50.00%
2016 Annual Long Term Equity Incentive Program (“2016 Annual EIP”) [Member] | Issued 03-28-2017 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	122,727
Vesting Period	3 years
Vesting Schedule (in hundredths)	25.00%
Shares Vested (in shares)	30,680
Unearned Compensation	$ 852
2015 Annual Long Term Equity Incentive Program (“2015 Annual EIP”) [Member] | Issued 03-30-2016 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	183,396
Vesting Period	3 years
Vesting Schedule (in hundredths)	25.00%
Shares Vested (in shares)	91,696	91,696
Unearned Compensation	$ 563	$ 868
2014 Annual Long Term Equity Incentive Program (“2014 Annual EIP”) [Member] | Issued 03-30-2015 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	128,832
Vesting Period	3 years
Vesting Schedule (in hundredths)	25.00%
Shares Vested (in shares)	96,623	96,623
Unearned Compensation	$ 113	$ 225
2017 Multi-Year Long Term Equity Incentive Program (“2017 Multi-Year EIP”) [Member] | Compensation Committee Approval Date March 10, 2017 [Member]
Unvested Share Awards [Abstract]
Performance Period	1/1/2017 to 12/31/2019
Unearned Compensation	$ 1,047
2016 Multi-Year Long Term Equity Incentive Program (“2016 Multi-Year EIP”) [Member] | Compensation Committee Approval Date March 17, 2016 [Member]
Unvested Share Awards [Abstract]
Performance Period	1/1/2016 to 12/31/2018
Unearned Compensation	$ 740	888
2015 Multi-Year Long Term Equity Incentive Program (“2015 Multi-Year EIP”) [Member] | Compensation Committee Approval Date March 18, 2015 [Member]
Unvested Share Awards [Abstract]
Performance Period	1/1/2015 to 12/31/2017
Unearned Compensation	$ 298	397
2014 Multi-Year Long Term Equity Incentive Program (“2014 Multi-Year EIP”) [Member] | Compensation Committee Approval Date April 11, 2014 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	61,057
LTIP Issuance Date	Mar. 28, 2017
Performance Period	1/1/2014 to 12/31/2016
Shares Vested (in shares)	30,524
Unearned Compensation	$ 221	283
Multi-Year LTIP [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	61,057
Shares Vested (in shares)	30,524
Unearned Compensation	$ 2,306	$ 1,568
Multi-year LTIP Trustee [Member]
Unvested Share Awards [Abstract]
Shares Vested (in shares)	2,505	2,505
Unearned Compensation	$ 128	$ 167
Multi-year LTIP Trustee [Member] | Issued 12-30-2016 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	5,000
Vesting Period	3 years
Vesting Schedule (in hundredths)	33.00%
Unearned Compensation	$ 90	$ 108
Multi-year LTIP Trustee [Member] | Issued 03-30-2016 [Member]
Unvested Share Awards [Abstract]
Shares Issued (in shares)	2,500
Vesting Period	3 years
Vesting Schedule (in hundredths)	33.00%
Shares Vested (in shares)	835	835
Unearned Compensation	$ 26	$ 35