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Property, Plant And Equipment
 12 Months Ended
Dec. 31, 2023
Property, Plant and Equipment [Abstract]  
Property, Plant And Equipment
Our property, plant and equipment on the Consolidated Balance Sheets are classified as follows: 
At December 31, (in millions)
20232022
Property, Plant and Equipment
Gas Distribution Utility
$18,154.5 $16,576.4 
Electric Utility
7,907.9 7,162.4 
Corporate274.2 271.7 
Construction Work in Process1,261.1 1,398.2 
Renewable Generation Assets(1)
1,434.4 702.2 
Non-Utility and Other1,450.0 1,440.4 
Total Property, Plant and Equipment$30,482.1 $27,551.3 
Accumulated Depreciation and Amortization
Gas Distribution Utility
$(3,924.4)$(3,678.1)
Electric Utility
(2,709.5)(2,557.4)
Corporate(174.2)(160.0)
Renewable Generation Assets(1)
(64.5)(29.7)
Non-Utility and Other(1,334.6)(1,283.5)
Total Accumulated Depreciation and Amortization$(8,207.2)$(7,708.7)
Net Property, Plant and Equipment$22,274.9 $19,842.6 
(1)Our renewable generation assets are part of our electric segment and represent Non-Utility Property, owned and operated by JVs between NIPSCO and unrelated tax equity partners, and depreciated straight-line over 30 years. Refer to Note 4, "Noncontrolling Interest," for additional information.

The weighted average depreciation provisions for utility plant, as a percentage of the original cost, for the periods ended December 31, 2023, 2022 and 2021 were as follows:
202320222021
Electric Operations3.5 %3.1 %3.4 %
Gas Distribution Operations2.4 %2.3 %2.2 %

We recognized depreciation expense of $756.9 million, $685.0 million and $672.1 million for the years ended 2023, 2022 and 2021, respectively. The 2023, 2022 and 2021, depreciation expense includes $12.5 million, $11.0 million, and $5.3 million related to the regulatory deferral of income associated with our JVs, which is not included in current rates. See Note 1, "Nature of Operations and Summary of Significant Accounting Policies - S. Noncontrolling Interest," for additional details.
Amortization of on-premise Software Costs. We amortized $77.5 million, $53.1 million and $49.4 million in 2023, 2022 and 2021, respectively, related to software recorded as intangible assets. Our unamortized software balance was $205.6 million and $190.1 million at December 31, 2023 and 2022, respectively.
Amortization of Cloud Computing Costs. We amortized $12.6 million, $11.1 million and $10.0 million in 2023, 2022 and 2021, respectively, related to cloud computing costs to "Operation and maintenance" expense. Our unamortized cloud computing balance was $32.2 million and $45.7 million at December 31, 2023 and 2022, respectively.