Condensed Consolidated Balance Sheet (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Trade receivables, allowance for doubtful accounts	$ 7,054	$ 7,306
Common stock, par value	$ 0	$ 0
Preferred Stock, 4 1/2% Cumulative
Percentage of cumulative preferred stock	4.50%	4.50%
Preferred stock, par value	$ 50	$ 50