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Deferred tax reconciliation (Details 5) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Income Tax Disclosure [Abstract] |  |  |
Change in net deferred income tax liability from the preceding table | $ 4,597 |  |
Deferred taxes associated with other comprehensive income | (825) |  |
Other | (5,821) |  |
Deferred income taxes | $ (2,049) | $ (25,356) | $ 54,963

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