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SCHEDULE I - Parent Company Information - Condensed Statements of Income - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Parent Company |  |  |
Equity in income of subsidiaries |  |  |
Equity in income of subsidiaries, tax | $ (30,990) | $ 5,168 | $ 4,037

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- Definition Represents the tax amount on earnings (losses) of affiliates and subsidiaries during the period. + References No definition available. + Details
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