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Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Statement of Comprehensive Income [Abstract] |  |
Net Income | $ 26,855 | $ 19,144
Other Comprehensive (Loss) Income, net of tax: |  |
Amortization of prior service cost, net of tax of $(5) and $(8), respectively | (14) | (11)
Net gain, net of tax of $41 and $77, respectively | 108 | 93
Cash Flow Hedges, net of tax: |  |
Unrealized (loss)/gain on commodity contract cash flow hedges, net of tax of ($756) and $192, respectively | (1,788) | 338
Total Other Comprehensive (Loss) Income, net of tax | (1,694) | 420
Comprehensive Income | $ 25,161 | $ 19,564

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