Business Segments (Reconciliation of Operating Profit (Loss) from Segments to Consolidated) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Segments [Abstract]
Income for reportable segments	$ 12,933	$ 12,438	$ 20,051	$ 21,708
Interest expense	(126)	(125)	(249)	(258)
Interest income	147	139	291	345
Other income	115	137	250	315
LIFO income (expense)	202	(14)	198	(254)
Equity in income of nonconsolidated investment	142	420	346	596
Corporate expense, cost of capital elimination and other unallocated charges	(3,206)	(1,900)	(5,359)	(3,913)
Income from continuing operations before income taxes	$ 10,207	$ 11,095	$ 15,528	$ 18,539