CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Dividends (in dollars per share)	$ 0.48	$ 0.48	$ 0.45
Accumulated Other Comprehensive Income (Loss)
Pension and postretirement plans, tax benefit (expense)	$ 207	$ 89	$ (429)
Interest rate swap, tax	$ 189
Retained Earnings
Dividends (in dollars per share)	$ 0.48	$ 0.48	$ 0.45
Retained Earnings \| Accounting Standards Update 2016-09
Deferred tax assets, net		$ 300

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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