Derivative Financial Instruments (Amounts Included in AOCL) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Derivative Gains Included in Accumulated Other Comprehensive Loss [Roll Forward] | |||
| Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax | $ (33,755) | $ (34,776) | $ (30,126) |
| Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax | 4,317 | (1,937) | (6,699) |
| Reclassification of net loss on cash flow hedges to income | 2,958 | 2,958 | 2,049 |
| Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax | $ (26,480) | $ (33,755) | $ (34,776) |