Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Utility plant:
Land	$ 45,672	$ 45,047
Depreciable plant and equipment	3,645,770	3,235,415
Construction work in progress	171,414	245,169
Intangible assets	27,567	24,854
Total utility plant	3,890,423	3,550,485
Less accumulated depreciation and amortization	(1,239,865)	(1,144,115)
Net utility plant	2,650,558	2,406,370
Current assets:
Cash and cash equivalents	44,555	42,653
Receivables:
Customers, net	44,025	32,058
Regulatory balancing accounts	96,241	38,225
Other, net	20,331	14,187
Unbilled revenue, net	34,069	34,879
Materials and supplies at weighted average cost	8,831	7,745
Taxes, prepaid expenses, and other assets	17,964	14,965
Total current assets	266,016	184,712
Other assets:
Regulatory assets	325,376	433,322
Goodwill	31,842	2,615
Other	120,456	84,289
Total other assets	477,674	520,226
TOTAL ASSETS	3,394,248	3,111,308
Capitalization:
Common stock, $0.01 par value; 68,000 shares authorized, 50,334 and 48,532 outstanding in 2020 and 2019, respectively	503	485
Additional paid-in capital	448,632	362,275
Retained earnings	472,209	417,146
Total common stockholders' equity	921,344	779,906
Long-term debt, net	781,100	786,754
Total capitalization	1,702,444	1,566,660
Current liabilities:
Current maturities of long-term debt, net	5,127	21,868
Short-term borrowings	370,000	175,100
Accounts payable	131,725	108,463
Regulatory balancing accounts	34,636	4,462
Accrued other taxes	4,477	4,445
Accrued interest	6,178	5,810
Other accrued liabilities	36,563	38,573
Total current liabilities	588,706	358,721
Deferred income taxes	276,032	222,590
Regulatory liabilities	180,718	211,413
Pension and postretirement benefits other than pensions	115,581	258,907
Advances for construction	195,625	191,062
Contributions in aid of construction	268,050	241,537
Other long-term liabilities	67,092	60,418
Commitments and contingencies
TOTAL CAPITALIZATION AND LIABILITIES	$ 3,394,248	$ 3,111,308