UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current Assets
Cash and cash equivalents	$ 61,955	$ 71,086
Accounts receivable, net	24,255	25,274
Income taxes receivable	10,329	4,705
Materials and supplies	8,807	9,789
Prepaid expenses and other	5,602	4,749
Deferred income taxes	1,022	832
Total current assets	111,970	116,435
Investments, including $2,325 and $2,064 carried at fair value	8,976	8,214
Property, plant and equipment, net	395,456	365,474
Other Assets
Intangible assets, net	71,673	74,942
Deferred charges and other assets, net	9,424	5,675
Net other assets	81,097	80,617
Total assets	597,499	570,740
Current Liabilities
Current maturities of long-term debt	0	1,977
Accounts payable	23,631	31,729
Advanced billings and customer deposits	11,161	11,190
Accrued compensation	3,852	2,671
Accrued liabilities and other	9,823	10,573
Total current liabilities	48,467	58,140
Long-term debt, less current maturities	230,200	230,200
Other Long-Term Liabilities
Deferred income taxes	64,954	57,896
Deferred lease payable	5,884	4,903
Asset retirement obligations	6,214	5,896
Other liabilities	6,893	5,857
Total other liabilities	83,945	74,552
Commitments and Contingencies
Shareholders' Equity
Common stock	25,908	24,688
Accumulated other comprehensive income (loss)	2,046	(863)
Retained earnings	206,933	184,023
Total shareholders' equity	234,887	207,848
Total liabilities and shareholders' equity	$ 597,499	$ 570,740