Deferred Charges, Goodwill And Other Assets, Net (Narrative) (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2017 |
Jun. 30, 2016 |
|
| Credit Risk Contract [Member] | ||||
| Derivative Instruments, Gain (Loss) [Line Items] | ||||
| Net liability | $ 400,000 | $ 400,000 | ||
| Settlement obligation | 400,000 | 400,000 | ||
| Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | ||||
| Derivative Instruments, Gain (Loss) [Line Items] | ||||
| Derivative notional amount | 675,000,000 | 675,000,000 | ||
| Ineffective increase to interest expense | 11,000 | $ (99,000) | (32,000) | $ (1,012,000) |
| Estimated additional amount to be reclassified to interest expense | 1,200,000 | |||
| Not Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | ||||
| Derivative Instruments, Gain (Loss) [Line Items] | ||||
| Amount of increase in the fair value of derivatives | $ 0 | $ 1,000 | $ 0 | $ 2,000 |