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Accounting Pronouncements Recently Issued Narrative - Impact of implementation of new accounting standards (Details) - USD ($) $ in Thousands | 6 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2019 | Dec. 31, 2018 | Mar. 31, 2018 | Dec. 31, 2017
Accounting Standards Update 2016-02 [Member] |  |  |  |
Change in other assets due to adoption of new ASU | $ 49,200 |  |  |
Change in other liabilities due to adoption of new ASU | $ 48,200 |  |  |
Accounting Standards Update 2016-01 [Member] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ 46 | $ 0
Retained Earnings [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  | $ 782 |  |
Retained Earnings [Member] | Accounting Standards Update 2016-01 [Member] |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ 46 | $ (157)

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- Definition Change in other assets due to adoption of new ASU + References No definition available. + Details
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- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. + References No definition available. + Details
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