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v3.25.4

Long-Term Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Instrument [Line Items] |  |
Total debt | $ 1,901,201 | $ 1,719,824
Unamortized debt premium and discount, net | (1,644) | (56)
Unamortized debt issuance costs | (9,234) | (9,216)
Current portion | (23,504) | (3,648)
Total long-term debt, less current portion | 1,866,819 | 1,706,904
H2O America |  |
Debt Instrument [Line Items] |  |
Total long-term debt, less current portion | 557,832 | 557,430
H2O America | Senior notes |  |
Debt Instrument [Line Items] |  |
Total debt | $ 560,000 | 560,000
H2O America | Senior notes | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 2.47% |
H2O America | Senior notes | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 3.53% |
SJWC | California Pollution Control Financing Authority Revenue Bond |  |
Debt Instrument [Line Items] |  |
Total debt | $ 630,000 | 575,000
SJWC | Senior notes |  |
Debt Instrument [Line Items] |  |
Total debt | $ 560,000 | 505,000
SJWC | Senior notes | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 3.00% |
SJWC | Senior notes | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 7.20% |
SJWC | Public Utility, Bonds | California Pollution Control Financing Authority Revenue Bond |  |
Debt Instrument [Line Items] |  |
Rate | 4.75% |
Total debt | $ 70,000 | 70,000
CTWS | Bank term loans |  |
Debt Instrument [Line Items] |  |
Total debt | $ 12,212 | 14,389
CTWS | Bank term loans | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 4.09% |
CTWS | Bank term loans | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 4.15% |
CWC |  |
Debt Instrument [Line Items] |  |
Total debt | $ 448,653 | 388,672
CWC | Senior notes |  |
Debt Instrument [Line Items] |  |
Total debt | $ 330,000 | 270,000
CWC | Senior notes | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 3.07% |
CWC | Senior notes | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 6.46% |
CWC | Public Utility, Bonds | Connecticut Innovations Revenue Bonds, variable rate |  |
Debt Instrument [Line Items] |  |
Total debt | $ 22,050 | 22,050
CWC | Bank term loans |  |
Debt Instrument [Line Items] |  |
Total debt | $ 96,295 | 96,295
CWC | Bank term loans | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 4.04% |
CWC | Bank term loans | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 4.75% |
CWC | State revolving fund loans | State revolving fund loans |  |
Debt Instrument [Line Items] |  |
Rate | 2.00% |
Total debt | $ 308 | 327
TWC |  |
Debt Instrument [Line Items] |  |
Total debt | $ 149,000 | 109,000
TWC | Senior notes |  |
Debt Instrument [Line Items] |  |
Rate | 6.27% |
Total debt | $ 15,000 | 15,000
TWC | Bank term loans |  |
Debt Instrument [Line Items] |  |
Total debt | $ 105,000 | 65,000
TWC | Bank term loans | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 4.01% |
TWC | Bank term loans | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 6.68% |
TWC | Seller financing debt |  |
Debt Instrument [Line Items] |  |
Total debt | $ 29,000 | 29,000
Interest rate effective percentage | 5.61% |
MWC |  |
Debt Instrument [Line Items] |  |
Total debt | $ 101,336 | 72,763
MWC | Bank term loans |  |
Debt Instrument [Line Items] |  |
Total debt | $ 85,000 | 60,000
MWC | Bank term loans | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 3.89% |
MWC | Bank term loans | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 6.47% |
MWC | State revolving fund loans | State revolving fund loans |  |
Debt Instrument [Line Items] |  |
Total debt | $ 16,336 | $ 12,763
MWC | State revolving fund loans | State revolving fund loans | Minimum |  |
Debt Instrument [Line Items] |  |
Rate | 0.00% |
MWC | State revolving fund loans | State revolving fund loans | Maximum |  |
Debt Instrument [Line Items] |  |
Rate | 2.23% |

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