CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Utility Plant
Plant in Service	$ 7,797,935	$ 7,073,292
Construction Work in Progress	320,931	627,382
Total Utility Plant	8,118,866	7,700,674
Accumulated Depreciation and Amortization	(2,786,839)	(2,645,333)
Total Utility Plant, Net	5,332,027	5,055,341
Investments and Other Property	81,958	76,299
Current Assets
Cash and Cash Equivalents	9,970	60,960
Accounts Receivable (Net of Allowance for Credit Losses of $10,044 and $13,260)	192,579	173,412
Fuel Inventory	26,971	21,946
Materials and Supplies	141,677	126,788
Less Current Portion	116,442	123,588
Derivative Instruments	19,406	16,094
Other	24,229	23,895
Total Current Assets	531,274	546,683
Regulatory and Other Assets
Regulatory Assets	267,669	318,474
Derivative Instruments	14,392	725
Other	94,420	92,605
Total Regulatory and Other Assets	376,481	411,804
Total Assets	6,321,740	6,090,127
Common Stock Equity:
Common Stock (No Par Value, 75,000,000 Shares Authorized, 32,139,434 Shares Outstanding as of December 31, 2021 and 2020)	1,696,539	1,646,539
Capital Stock Expense	(6,357)	(6,357)
Retained Earnings	850,942	712,197
Accumulated Other Comprehensive Loss	(9,915)	(10,942)
Total Common Stock Equity	2,531,209	2,341,437
Preferred Stock (No Par Value, 1,000,000 Shares Authorized, None Outstanding as of December 31, 2021 and 2020)	0	0
Long-Term Debt, Net	2,134,534	1,814,059
Total Capitalization	4,665,743	4,155,496
Current Liabilities
Current Maturities of Long-Term Debt, Net	0	249,752
Borrowings Under Credit Agreement	15,000	0
Accounts Payable	139,329	109,461
Accrued Taxes Other than Income Taxes	53,534	50,278
Accrued Employee Expenses	36,217	35,129
Accrued Interest	16,265	16,337
Regulatory Liabilities	111,356	151,189
Customer Deposits	12,791	16,450
Derivative Instruments	15,854	27,789
Other	25,358	22,031
Total Current Liabilities	425,704	678,416
Regulatory and Other Liabilities
Deferred Income Taxes, Net	548,750	492,919
Regulatory Liabilities	352,226	390,164
Pension and Other Postretirement Benefits	120,020	163,652
Derivative Instruments	3,848	37,958
Other	205,449	171,522
Total Regulatory and Other Liabilities	1,230,293	1,256,215
Commitments and Contingencies
Total Capitalization and Other Liabilities	$ 6,321,740	$ 6,090,127