Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Allowance for uncollectible accounts	$ 170	$ 225
Capitalization:
Common stock, par value	$ 0.521	$ 0.521
Common stock, shares authorized	36,000,000	36,000,000
Common stock, shares issued	20,169,211	18,670,566
Common stock, shares outstanding	20,169,211	18,670,566