Consolidated Statements of Cash Flows Supplemental Disclosures (Net Cash Paid or Received) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Supplemental Cash Flow Elements [Abstract] | |||
| Interest paid, net of amounts capitalized | $ 90,998 | $ 84,546 | $ 76,796 |
| X | ||||||||||
- Definition The amount of cash paid for interest during the period net of cash paid for interest that is capitalized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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