XML 117 R98.htm IDEA: XBRL DOCUMENT v3.24.3
Note 15 - Regulatory Matters - Regulatory Assets and Liabilities (Details) - USD ($)
$ in Millions
Sep. 30, 2024
Sep. 30, 2023
Regulatory Asset, Current $ 115.4 $ 348.3
Regulatory Assets Noncurrent 1,251.8 1,249.2
Total Regulatory Assets 1,367.2 1,597.5
Regulatory Liability, Current 49.5 7.3
Regulatory liabilities 535.5 472.4
Total Regulatory Liabilities 585.0 479.7
Spire Missouri [Member]    
Regulatory Asset, Current 84.0 293.1
Regulatory Assets Noncurrent 588.0 617.6
Total Regulatory Assets 672.0 910.7
Regulatory Liability, Current 10.2 0.0
Regulatory liabilities 443.3 389.4
Total Regulatory Liabilities 453.5 389.4
Spire Alabama Inc [Member]    
Regulatory Asset, Current 19.2 41.6
Regulatory Assets Noncurrent 642.0 606.9
Total Regulatory Assets 661.2 648.5
Regulatory Liability, Current 33.8 0.0
Regulatory liabilities 28.3 21.2
Total Regulatory Liabilities 62.1 21.2
Unamortized Purchased Gas Adjustments Asset [Member]    
Regulatory Asset, Current 28.9 293.2
Regulatory Assets Noncurrent 1.2 23.0
Regulatory Liability, Current 42.3 0.0
Regulatory liabilities 17.2 11.2
Unamortized Purchased Gas Adjustments Asset [Member] | Spire Missouri [Member]    
Regulatory Asset, Current 28.1 269.4
Regulatory Assets Noncurrent 1.2 23.0
Regulatory Liability, Current 10.2 0.0
Regulatory liabilities 17.2 11.2
Unamortized Purchased Gas Adjustments Asset [Member] | Spire Alabama Inc [Member]    
Regulatory Asset, Current 0.0 21.7
Regulatory Assets Noncurrent 0.0 0.0
Regulatory Liability, Current 30.9 0.0
Regulatory liabilities 0.0 0.0
Other Regulatory Assets (Liabilities) [Member]    
Regulatory Asset, Current 86.5 55.1
Regulatory Assets Noncurrent 133.2 131.2
Regulatory Liability, Current 7.2 7.3
Regulatory liabilities 37.6 21.4
Other Regulatory Assets (Liabilities) [Member] | Spire Missouri [Member]    
Regulatory Asset, Current 55.9 23.7
Regulatory Assets Noncurrent 119.6 116.0
Regulatory Liability, Current 0.0 0.0
Regulatory liabilities 33.2 16.5
Other Regulatory Assets (Liabilities) [Member] | Spire Alabama Inc [Member]    
Regulatory Asset, Current 19.2 19.9
Regulatory Assets Noncurrent 0.8 0.9
Regulatory Liability, Current 2.9 0.0
Regulatory liabilities 3.2 3.3
Deferred Income Tax Charge [Member]    
Regulatory Assets Noncurrent 150.7 144.5
Deferred Income Tax Charge [Member] | Spire Missouri [Member]    
Regulatory Assets Noncurrent 142.7 136.2
Deferred Income Tax Charge [Member] | Spire Alabama Inc [Member]    
Regulatory Assets Noncurrent 1.8 2.0
Pension and Other Postretirement Plans Costs [Member]    
Regulatory Assets Noncurrent 237.5 261.0
Regulatory liabilities 232.9 185.2
Pension and Other Postretirement Plans Costs [Member] | Spire Missouri [Member]    
Regulatory Assets Noncurrent 166.5 189.1
Regulatory liabilities 196.6 156.5
Pension and Other Postretirement Plans Costs [Member] | Spire Alabama Inc [Member]    
Regulatory Assets Noncurrent 68.2 67.8
Regulatory liabilities 25.1 17.9
Removal Costs [Member]    
Regulatory Assets Noncurrent 668.2 633.2
Regulatory liabilities 133.6 126.6
Removal Costs [Member] | Spire Missouri [Member]    
Regulatory Assets Noncurrent 97.0 97.0
Regulatory liabilities 94.5 90.4
Removal Costs [Member] | Spire Alabama Inc [Member]    
Regulatory Assets Noncurrent 571.2 536.2
Regulatory liabilities 0.0 0.0
Renewable Energy Program [Member]    
Regulatory Assets Noncurrent 61.0 56.3
Renewable Energy Program [Member] | Spire Missouri [Member]    
Regulatory Assets Noncurrent 61.0 56.3
Renewable Energy Program [Member] | Spire Alabama Inc [Member]    
Regulatory Assets Noncurrent 0.0 0.0
Estimated Deferred Taxes Due to Customers [Member]    
Regulatory liabilities 114.2 128.0
Estimated Deferred Taxes Due to Customers [Member] | Spire Missouri [Member]    
Regulatory liabilities 101.8 114.8
Estimated Deferred Taxes Due to Customers [Member] | Spire Alabama Inc [Member]    
Regulatory liabilities $ 0.0 $ 0.0