Condensed Consolidated Balance Sheets Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Allowance for doubtful accounts	$ 7,098	$ 6,868
Common, stated value per share	$ 20.00	$ 20.00
Authorized	50,000,000	20,000,000
Issued to voting trustees	13,217,044	12,844,501
Issued to shareholders	2,779,499	2,740,489
In treasury, at cost	(435,848)	(84,566)
Outstanding Common Stock	15,560,695	15,500,424