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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Net Income | $ 86,847 | $ 82,345 | $ 72,439
Unrealized Gain (Loss) on Available-for-Sale Securities: |  |  |
Reversal of Previously Recognized Losses (Gains) Realized on Sale of Investments and Included in Other Income During Period | 16 | (105) | (15)
Unrealized Gains (Losses) Arising During Period | 147 | (61) | 115
Income Tax (Expense) Benefit | (34) | 35 | (35)
Change in Unrealized Gain (Loss) on Available-for-Sale Securities – net-of-tax | 129 | (131) | 65
Pension and Postretirement Benefit Plans: |  |  |
Actuarial (Losses) Gains net of Regulatory Allocation Adjustment | (2,779) | 1,919 | (3,791)
Amortization of Unrecognized Postretirement Benefit Losses and Costs (note 11) | 565 | 985 | 629
Income Tax Benefit (Expense) | 576 | (755) | 1,266
Adjustment to Income Tax Expense Related to 2017 Tax Cuts and Jobs Act | 0 | (531) | 0
Pension and Postretirement Benefit Plans – net-of-tax | (1,638) | 1,618 | (1,896)
Total Other Comprehensive (Loss) Income | (1,509) | 1,487 | (1,831)
Total Comprehensive Income | $ 85,338 | $ 83,832 | $ 70,608

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