Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Common stock, par value	$ 0.50	$ 0.50
Common stock, Authorized shares	30,000,000	30,000,000
Common stock, Issued shares	20,082,157	19,975,706
Common stock, outstanding shares	20,082,157	19,975,706
Property and equipment, net	$ 140,086	$ 128,430
Centennial
Property and equipment, net	$ 71,258	$ 66,412