CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
NET INCOME	$ 39,985	$ 67,262	$ 59,726
Pension and other postretirement benefit plans:
Net actuarial gain (loss), net of tax of: (2019 - $2,308; 2018 - $477; 2017 - $1,682)	6,657	(1,376)	(2,640)
Pension settlement expense, including termination expense, net of tax of: (2019 - $1,167; 2018 - $3,327; 2017 - $1,617)	7,338	9,598	2,539
Amortization of unrecognized net periodic benefit costs, net of tax of: (2019 - $314; 2018 - $740; 2017 - $1,446)
Net actuarial loss	931	2,204	2,388
Prior service credit	(25)	(69)	(116)
Interest rate swap and foreign currency translation:
Change in unrealized income (loss) on interest rate swap, net of tax of:(2019 - $357)	(1,007)
Change in unrealized income (loss) on interest rate swap, net of tax of:(2018 - $84; 2017 - $402)		236	621
Change in foreign currency translation, net of tax of: (2019 - $194; 2018 - $241; 2017 - $33)	547	(681)	51
OTHER COMPREHENSIVE INCOME, net of tax	14,441	9,912	2,843
TOTAL COMPREHENSIVE INCOME	$ 54,426	$ 77,174	$ 62,569

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