Equity and Noncontrolling Interest - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity Class Of Treasury Stock [Line Items]
Common Stock Par Value	$ 1	$ 1
Common Stock Shares Authorized	30,000,000	30,000,000
Common Stock Shares, Issued	13,277,832	13,288,113
Shares issued for equity based comp plans	55,982
Shares issued for ESPP	6,130
Shares issued for Options exercise and Other activity	11,486
Common Stock Voting Rights	Holders of record of the Company’s common stock for a period of less than 36 consecutive calendar months or less are entitled to one vote per share of common stock. Holders of record of the Company’s common stock for a period greater than 36 consecutive calendar months are entitled to 10 votes per share of common stock.
Preferred Stock Shares Authorized	10,000,000
Preferred Stock Par Or Stated Value Per Share	$ 1
Stock Repurchased And Retired During Period Shares	83,879
Payments For Repurchase Of Common Stock	$ 5,859	$ 7,276	$ 0
2015 Share Repurchase [Member]
Equity Class Of Treasury Stock [Line Items]
Stock Repurchase Program Authorized Amount	$ 100,000	$ 100,000
Stock Repurchased And Retired During Period Shares	83,879	87,386
Payments For Repurchase Of Common Stock	$ 5,900	$ 7,300
Cost of Sales [Member]
Concentration Risk [Line Items]
Percentage of domestic pension assets	30.00%	30.00%
Operating Expense [Member]
Concentration Risk [Line Items]
Percentage of domestic pension assets	70.00%	70.00%