Short-Term and Long-Term Debt Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Jul. 22, 2010
Debt Instrument [Line Items]
Revolving credit facility, amount outstanding	$ 20,000	$ 24,200
Senior unsecured notes	30,000	30,000	30,000
Term loans	8,468	7,579
Long-term debt	58,468	61,779
Less current portion	8,434	6,992
Long-term debt, excluding current maturities	50,034	54,787
Swing-line borrowings [Member]
Debt Instrument [Line Items]
Revolving credit facility, amount outstanding	0	0
Prime rate borrowings [Member]
Debt Instrument [Line Items]
Revolving credit facility, amount outstanding	0	9,200
LIBOR borrowings [Member]
Debt Instrument [Line Items]
Revolving credit facility, amount outstanding	$ 20,000	$ 15,000