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Investments (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2008
Investments, Other Investments [Line Items] |  |  |  |  |  |
Goodwill, Impairment Loss |  |  | $ 0 | $ 46,792 | $ 0 |
Gain (loss) on investment accounted for under the fair value method |  |  | $ (10,900) | (30,600) | (33,800) |
kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Other Interest and Dividend Income |  | $ 17,600 |  |  |  |
Total cash invested in private company |  |  |  |  |  | $ 7,500
Ownership interest percentage |  |  | 18.00% |  |  |
Gain (loss) on investment accounted for under the fair value method | [1] |  | $ (28,482) | (30,600) | (33,800) |
Unrealized gain (loss) on investments, net of tax |  |  | 23,400 | 23,900 |  |
Other Assets and Deferred Charges [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Carrying value |  |  | 95,500 | 84,600 |  |
Alleghany and Bath County, Virginia |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Gain (loss) on investment accounted for under the fair value method |  |  | 0 | 186 | 0 |
Unrealized Gain (Loss) on Investment Property |  |  | $ 0 | $ 186 | $ 0 |
DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate |  |  | 10.00% | 15.00% |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 50.00% |  |  |
EBITDA Multiple Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 80.00% |  |  |
40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 40.00% |  |  |
30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 30.00% |  |  |
20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 20.00% |  |  |
10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 10.00% |  |  |
0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Weighting of EBITDA Multiple Method versus DCF Method |  |  | 0.00% |  |  |
7.6x [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
EV-to-Adjusted EBITDA Multiple |  |  | 7.0 x |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
7.6x [Domain] | 40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
7.6x [Domain] | 30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
7.6x [Domain] | 20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
7.6x [Domain] | 10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
7.6x [Domain] | 0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
8.6x [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
EV-to-Adjusted EBITDA Multiple |  |  | 8.0 x |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
8.6x [Domain] | 40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
8.6x [Domain] | 30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
8.6x [Domain] | 20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
8.6x [Domain] | 10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
8.6x [Domain] | 0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
9.6x [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
EV-to-Adjusted EBITDA Multiple |  |  | 9.0 x |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
9.6x [Domain] | 40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
9.6x [Domain] | 30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
9.6x [Domain] | 20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
9.6x [Domain] | 10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
9.6x [Domain] | 0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
10.6x [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
EV-to-Adjusted EBITDA Multiple |  |  | 10.0x |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
10.6x [Domain] | 40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
10.6x [Domain] | 30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
10.6x [Domain] | 20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
10.6x [Domain] | 10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
10.6x [Domain] | 0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
11.6x [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
EV-to-Adjusted EBITDA Multiple |  |  | 11.0x |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | $ 100 |  |  |
11.6x [Domain] | 40% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
11.6x [Domain] | 30% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
11.6x [Domain] | 20% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
11.6x [Domain] | 10% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
11.6x [Domain] | 0% [Domain] | DCF Method for Fair Value Estimate [Member] | kaleo |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Fair Value Sensitivity Analysis: Weighting to DCF Method at Varied EV-to-Adjusted EBITDA Multiple |  |  | 100 |  |  |
Personal Care Materials [Member] |  |  |  |  |  |
Investments, Other Investments [Line Items] |  |  |  |  |  |
Goodwill, Impairment Loss |  |  | $ 0 | $ (46,792) |  |
[1] | See Notes 1, 3, 4 and 17 for more information on losses associated with plant shutdowns, asset impairments and restructurings, unusual items, gains or losses from sale of assets, gains or losses on an investment accounted for under the fair value method and other items.

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