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Property, Plant And Equipment
 12 Months Ended
Dec. 31, 2024
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)
20242023
Property, Plant and Equipment
Gas Distribution Utility
$20,007.2 $18,154.5 
Electric Utility
8,666.8 7,907.9 
Corporate248.1 274.2 
Construction Work in Process2,084.7 1,261.1 
JV Renewable Generation Assets(1)
1,434.2 1,434.4 
Non-Utility and Other1,711.9 1,450.0 
Total Property, Plant and Equipment$34,152.9 $30,482.1 
Accumulated Depreciation and Amortization
Gas Distribution Utility
$(4,166.8)$(3,924.4)
Electric Utility
(2,707.8)(2,709.5)
Corporate(163.4)(174.2)
JV Renewable Generation Assets(1)
(110.4)(64.5)
Non-Utility and Other(1,550.6)(1,334.6)
Total Accumulated Depreciation and Amortization$(8,699.0)$(8,207.2)
Net Property, Plant and Equipment$25,453.9 $22,274.9 
(1)These JV renewable generation assets owned and operated by JVs between NIPSCO and unrelated tax equity partners represent Non-Utility Property, are depreciated straight-line over 30 years and are part of our NIPSCO Operations segment. Refer to Note 4, "Noncontrolling Interests," for additional information.

The weighted average depreciation provisions for utility plant, as a percentage of the original cost, for the periods ended December 31, 2024, 2023 and 2022 were as follows:
202420232022
NIPSCO Operations3.0 %3.0 %2.7 %
Columbia Operations
2.6 %2.5 %2.4 %

We recognized depreciation expense of $820.4 million, $756.9 million and $685.0 million for the years ended 2024, 2023 and 2022, respectively. The 2024, 2023 and 2022, depreciation expense includes $58.9 million, $12.5 million, and $11.0 million
related to the regulatory deferral of income associated with our JVs. 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 $85.2 million, $77.5 million and $53.1 million in 2024, 2023 and 2022, respectively, related to software recorded as intangible assets. Our unamortized software balance was $236.1 million and $205.6 million at December 31, 2024 and 2023, respectively.
Amortization of Cloud Computing Costs. We amortized $17.7 million, $12.6 million and $11.1 million in 2024, 2023 and 2022, respectively, related to cloud computing costs to "Operation and maintenance" expense. Our unamortized cloud computing balance was $77.5 million and $32.2 million at December 31, 2024 and 2023, respectively.