Deferred Charges, Goodwill And Other Assets, Net (Schedule Of Cash Flow Hedging, Derivative Financial Instruments On The Income Statement) (Details) - Not Designated as Hedging Instrument [Member] - Interest Rate Swaps [Member] - Cash Flow Hedging [Member] - USD ($)
$ in Thousands |
3 Months Ended |
6 Months Ended |
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
|
| Amount of Gain or (Loss) Recognized in OCI on Derivative (Effective Portion) |
$ 2,428
|
$ (2,129)
|
$ 7,654
|
$ (1,494)
|
| Interest Expense [Member] |
|
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
|
| Amount of Gain or (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) |
640
|
(776)
|
720
|
(1,368)
|
| Interest And Other Investment Income (Loss) [Member] |
|
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
|
| Amount of Gain or (Loss) Recognized in Income on Derivative (Ineffective Portion, Reclassification for Forecasted Transactions No Longer Probable of Occurring and Amount Excluded from Effectiveness Testing) |
$ (100)
|
$ 11
|
$ (174)
|
$ (32)
|