Unsecured Revolving Credit Facility And Term Loans (Schedule Of Defined Leverage Ratio) (Details)
|
12 Months Ended |
Dec. 31, 2017 |
|---|
| 45% Unsecured Term Loan Leverage Ratio [Member] |
|
| Debt Instrument [Line Items] |
|
| Spread over LIBOR |
1.45%
|
| 45% Unsecured Term Loan Leverage Ratio [Member] | Maximum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
45.00%
|
| 45% And 50% Unsecured Term Loan Leverage Ratio [Member] |
|
| Debt Instrument [Line Items] |
|
| Spread over LIBOR |
1.55%
|
| 45% And 50% Unsecured Term Loan Leverage Ratio [Member] | Minimum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
45.00%
|
| 45% And 50% Unsecured Term Loan Leverage Ratio [Member] | Maximum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
50.00%
|
| 50% And 55% Unsecured Term Loan Leverage Ratio [Member] |
|
| Debt Instrument [Line Items] |
|
| Spread over LIBOR |
1.65%
|
| 50% And 55% Unsecured Term Loan Leverage Ratio [Member] | Minimum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
50.00%
|
| 50% And 55% Unsecured Term Loan Leverage Ratio [Member] | Maximum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
55.00%
|
| 55% Unsecured Term Loan Leverage Ratio [Member] |
|
| Debt Instrument [Line Items] |
|
| Spread over LIBOR |
1.95%
|
| 55% Unsecured Term Loan Leverage Ratio [Member] | Minimum [Member] |
|
| Debt Instrument [Line Items] |
|
| Leverage ratio |
55.00%
|