CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Cash dividends, per share (in dollars per share)	$ 0.36	$ 0.28	$ 0.2
Unrealized gain (loss) on foreign exchange contracts, tax	$ 45	$ 14	$ 31
Unrealized gain (loss) on interest rate swap contracts, tax	230	444	136
Change in pension and post retirement benefit plans, tax	$ 2,790	$ 10,279	$ 5,887