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Pension, Savings, And Other Employee Benefits (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Estimated social security benefits age |  | 65 years |  |
Contributions to qualified plans | $ 165,000 | $ 0 | $ 165,000 |
Savings Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer investment in qualified defined contribution plan |  | 100.00% | 100.00% |
Maximum percent of employee pre-tax contributions that may be matched by the Company (percent) |  | 6.00% | 6.00% |
Non-Qualified Plans | Pension and Postretirement Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Contributions to qualified plans |  |  |  | $ 5,100
Expected pension contribution |  | $ 5,000 |  |

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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of cash or cash equivalents contributed by the entity to fund its pension plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585 + Details
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