CONDENSED CONSOLIDATED BALANCE SHEET (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current Assets:
Cash and cash equivalents	$ 10,921	$ 9,822
Restricted cash	8,236	6,700
Accounts receivable, net	129,195	143,695
Inventories	62,623	54,161
Regulatory assets	26,142	40,301
Deferred income taxes	30,255	37,143
Other	13,289	11,306
Total current assets	280,661	303,128
Property, plant, and equipment, net	2,573,562	2,435,590
Goodwill	355,128	355,128
Regulatory assets	395,746	367,890
Other noncurrent assets	28,553	23,797
Total assets	3,633,650	3,485,533
Current Liabilities:
Current maturities of capital leases	1,659	1,612
Short-term borrowings	102,980	122,934
Accounts payable	63,390	83,746
Accrued expenses	209,719	192,548
Regulatory liabilities	40,216	48,425
Total current liabilities	417,964	449,265
Long-term capital leases	30,315	31,562
Long-term debt	1,055,091	1,055,074
Deferred income taxes	397,856	363,928
Noncurrent regulatory liabilities	343,597	276,618
Other noncurrent liabilities	384,545	375,054
Total liabilities	2,629,368	2,551,501
Commitments and Contingencies (Note 14)
Shareholders' Equity:
Common stock, par value $0.01; authorized 200,000,000 shares; issued and outstanding 42,059,560, and 38,462,477 respectively; Preferred stock, par value $0.01; authorized 50,000,000 shares; none issued	421	408
Treasury stock at cost	(91,809)	(90,702)
Paid-in capital	896,242	849,218
Retained earnings	197,579	172,791
Accumulated other comprehensive income	1,849	2,317
Total shareholders' equity	1,004,282	934,032
Total liabilities and shareholders' equity	$ 3,633,650	$ 3,485,533