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Basis of Financial Reporting - Narrative (Details) - USD ($) $ in Thousands | Jan. 01, 2019 | Sep. 30, 2019 | Dec. 31, 2018 | Sep. 30, 2018
--- | --- | --- | --- | ---
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Operating lease liabilities |  | $ 35,237 |  |
Right of use assets |  | 34,264 |  |
Total assets deconsolidated |  | 23,936,719 | $ 25,220,968 | $ 25,104,925
Total liabilities deconsolidated |  | $ 21,582,054 | $ 22,906,189 |
Accounting Standards Update 2016-02 |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Operating lease liabilities | $ 33,700 |  |  |
Right of use assets | 32,800 |  |  |
Failed Sale-Leaseback Transaction | Accounting Standards Update 2016-02 |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Total assets deconsolidated | 43,800 |  |  |
Total liabilities deconsolidated | 34,800 |  |  |
Reduction to noncontrolling interest | $ 6,100 |  |  |

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