XML 59 R40.htm IDEA: XBRL DOCUMENT
v3.20.4

Summary of Significant Accounting Policies - Balancing and Memorandum Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Revenue accounts: |  |  |
Beginning Balance | $ (1,940) | $ 25,549 |
Regulatory Asset Increase (Decrease) | 2,516 | (4,984) |
Refunds (Collections) Adjustments | 9,467 | (22,505) |
Ending Balance | 10,043 | (1,940) | $ 25,549
Cost-recovery accounts: |  |  |
Beginning Balance | 7,223 | 8,864 |
Regulatory Asset Increase (Decrease) | 8,324 | 962 |
Refunds (Collections) Adjustments | (127) | (2,603) |
Ending Balance | 15,420 | 7,223 | 8,864
Balancing and Memorandum Account [Roll Forward] |  |  |
Beginning Balance | 5,283 | 34,413 |
Regulatory Asset Increase (Decrease) | 10,840 | (4,022) |
Refunds (Collections) Adjustments | 9,340 | (25,108) |
Ending Balance | 25,463 | 5,283 | 34,413
Monterey WRAM |  |  |
Revenue accounts: |  |  |
Beginning Balance | 7,015 | 6,847 |
Regulatory Asset Increase (Decrease) | 2,464 | 4,582 |
Refunds (Collections) Adjustments | 2,598 | (4,414) |
Ending Balance | 12,077 | 7,015 | 6,847
2014 - 2017 WCMA |  |  |
Revenue accounts: |  |  |
Beginning Balance | 708 | 7,750 |
Regulatory Asset Increase (Decrease) | 0 | 0 |
Refunds (Collections) Adjustments | (42) | (7,042) |
Ending Balance | 666 | 708 | 7,750
2018 WCMA |  |  |
Revenue accounts: |  |  |
Beginning Balance | 0 | 9,386 |
Regulatory Asset Increase (Decrease) |  | (9,386) |
Refunds (Collections) Adjustments |  | 0 |
Ending Balance |  | 0 | 9,386
2012 General Rate Case true-up |  |  |
Revenue accounts: |  |  |
Beginning Balance | 752 | 11,328 |
Regulatory Asset Increase (Decrease) | 0 | 96 |
Refunds (Collections) Adjustments | 0 | (10,672) |
Ending Balance | 752 | 752 | 11,328
Cost of capital memorandum accounts |  |  |
Revenue accounts: |  |  |
Beginning Balance | (1,553) | (1,523) |
Regulatory Asset Increase (Decrease) | (8) | (30) | (1,379)
Refunds (Collections) Adjustments | 0 | 0 |
Ending Balance | (1,561) | (1,553) | (1,523)
Tax memorandum account |  |  |
Revenue accounts: |  |  |
Beginning Balance | (6,643) | (6,504) |
Regulatory Asset Increase (Decrease) | (2) | (139) | (6,504)
Refunds (Collections) Adjustments | 6,978 | 0 |
Ending Balance | 333 | (6,643) | (6,504)
Water supply costs |  |  |
Cost-recovery accounts: |  |  |
Beginning Balance | 4,328 | 9,617 |
Regulatory Asset Increase (Decrease) | 3,828 | 207 |
Refunds (Collections) Adjustments | (33) | (5,496) |
Ending Balance | 8,123 | 4,328 | 9,617
Pension |  |  |
Cost-recovery accounts: |  |  |
Beginning Balance | 2,449 | (1,843) |
Regulatory Asset Increase (Decrease) | 1,008 | 745 |
Refunds (Collections) Adjustments | 21 | 3,547 |
Ending Balance | 3,478 | 2,449 | (1,843)
PRVMA |  |  |
Cost-recovery accounts: |  |  |
Beginning Balance | 0 |  |
Regulatory Asset Increase (Decrease) | 1,219 |  |
Refunds (Collections) Adjustments | (111) |  |
Ending Balance | 1,108 | 0 |
CEMA |  |  |
Cost-recovery accounts: |  |  |
Beginning Balance | 0 |  |
Regulatory Asset Increase (Decrease) | 2,266 |  |
Refunds (Collections) Adjustments | 0 |  |
Ending Balance | 2,266 | 0 |
All others |  |  |
Revenue accounts: |  |  |
Beginning Balance | (2,219) | (1,735) |
Regulatory Asset Increase (Decrease) | 62 | (107) |
Refunds (Collections) Adjustments | (67) | (377) |
Ending Balance | (2,224) | (2,219) | (1,735)
Cost-recovery accounts: |  |  |
Beginning Balance | 446 | 1,090 |
Regulatory Asset Increase (Decrease) | 3 | 10 |
Refunds (Collections) Adjustments | (4) | (654) |
Ending Balance | $ 445 | $ 446 | $ 1,090

X
- Definition Balancing and Memorandum Account, Net + References No definition available. + Details
Name: | sjw_BalancingAndMemorandumAccountNet
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Balancing and Memorandum Account, Increase (Decrease) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumAccountIncreaseDecrease
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Balancing and Memorandum Account, Refunds (Collections) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumAccountRefundsCollections
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Balancing and Memorandum Account [Roll Forward] + References No definition available. + Details
Name: | sjw_BalancingandMemorandumAccountRollForward
Namespace Prefix: | sjw_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Balancing and Memorandum Cost Recovery Account, Increase (Decrease) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumCostRecoveryAccountIncreaseDecrease
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Balancing and Memorandum Cost Recovery Account, Net + References No definition available. + Details
Name: | sjw_BalancingandMemorandumCostRecoveryAccountNet
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Balancing and Memorandum Cost Recovery Account, Refunds (Collections) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumCostRecoveryAccountRefundsCollections
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Balancing and Memorandum Cost Recovery Account [Roll Forward] + References No definition available. + Details
Name: | sjw_BalancingandMemorandumCostRecoveryAccountRollForward
Namespace Prefix: | sjw_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Balancing and Memorandum Revenue Account, Increase (Decrease) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumRevenueAccountIncreaseDecrease
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Balancing and Memorandum Revenue Accounting, Net + References No definition available. + Details
Name: | sjw_BalancingandMemorandumRevenueAccountNet
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Balancing and Memorandum Revenue Account, Refunds (Collections) + References No definition available. + Details
Name: | sjw_BalancingandMemorandumRevenueAccountRefundsCollections
Namespace Prefix: | sjw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Balancing and Memorandum Revenue Account [Roll Forward] + References No definition available. + Details
Name: | sjw_BalancingandMemorandumRevenueAccountRollForward
Namespace Prefix: | sjw_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_MontereyWRAMMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_A20142017WCMAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_A2018WCMAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_A2012GeneralRateCaseTrueupMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_CostofcapitalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_TaxmemorandumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_WaterSupplyBalancingAccountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_PensionBalancingAccountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_PRVMAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_CEMAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=sjw_OtherRegulatoryAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |