Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Cash and cash equivalents	$ 301,704	$ 305,551
Restricted cash	5,912	5,911
Accounts receivable and unbilled revenues, net	359,807	344,213
Available-for-sale investment securities, at fair value	2,621,375	2,574,618
Held-to-maturity investment securities, at amortized cost	517,150	522,270
Stock in Federal Home Loan Bank, at cost	10,000	10,000
Loans held for investment, net	5,117,522	5,139,984
Loans held for sale, at lower of cost or fair value	7,961	10,404
Property, plant and equipment, net of accumulated depreciation	5,411,746	5,392,068
Operating lease right-of-use assets	136,207	122,416
Regulatory assets	559,161	565,543
Other	777,694	747,469
Goodwill	82,190	82,190
Total assets	15,908,429	15,822,637
Liabilities
Accounts payable	240,296	205,544
Interest and dividends payable	33,519	19,889
Deposit liabilities	8,289,272	8,172,212
Short-term borrowings—other than bank	71,491	53,998
Other bank borrowings	137,385	88,305
Long-term debt, net—other than bank	2,316,046	2,321,937
Deferred income taxes	340,246	384,760
Operating lease liabilities	151,832	136,760
Regulatory liabilities	1,003,444	996,768
Defined benefit pension and other postretirement benefit plans liability	341,845	348,072
Other	645,118	669,215
Total liabilities	13,570,494	13,397,460
Preferred stock of subsidiaries - not subject to mandatory redemption	34,293	34,293
Commitments and contingencies (Notes 3 and 4)
Shareholders’ equity
Preferred stock, no par value, authorized 10,000,000 shares; issued: none	0	0
Common stock, no par value, authorized 200,000,000 shares; issued and outstanding: 109,431,346 shares and 109,311,785 shares at March 31, 2022 and December 31, 2021, respectively	1,684,547	1,685,496
Retained earnings	788,787	757,921
Accumulated other comprehensive loss, net of tax benefits	(169,692)	(52,533)
Total shareholders’ equity	2,303,642	2,390,884
Total liabilities and shareholders’ equity	$ 15,908,429	$ 15,822,637