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Segment and Non-Tariffed Business Reporting (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) subsidiary | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |
Number of subsidiaries | subsidiary |  |  |  | 4 |  |
Operating revenue |  | $ 165,863 | $ 113,997 | $ 428,826 | $ 294,644 |
Operating expense |  | 123,980 | 96,913 | 335,446 | 243,181 |
Operating income (loss) |  | 41,883 | 17,084 | 93,380 | 51,463 |
Net income (loss) |  | 26,093 | 9,478 | 48,231 | 28,889 |
Depreciation and amortization |  | 22,417 | 15,122 | 66,552 | 45,368 |
Interest on long-term debt and other interest expense |  | 13,174 | 6,588 | 39,638 | 19,093 |
Provision for income taxes |  | 4,578 | 2,565 | 9,226 | 8,802 |
Assets |  | 3,259,714 | 2,022,382 | 3,259,714 | 2,022,382 | $ 3,132,470
Water Utility Services | Regulated |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue |  | 161,646 | 110,218 | 416,085 | 285,138 |
Operating expense |  | 119,885 | 89,924 | 323,087 | 226,073 |
Operating income (loss) |  | 41,761 | 20,294 | 92,998 | 59,065 |
Net income (loss) |  | 25,053 | 10,964 | 53,117 | 30,726 |
Depreciation and amortization |  | 21,782 | 14,712 | 64,654 | 44,159 |
Interest on long-term debt and other interest expense |  | 8,112 | 6,044 | 24,575 | 17,434 |
Provision for income taxes |  | 9,450 | 2,912 | 16,101 | 9,142 |
Assets |  | 3,131,778 | 1,556,049 | 3,131,778 | 1,556,049 |
Water Utility Services | Non-tariffed |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue |  | 2,814 | 2,426 | 8,524 | 5,418 |
Operating expense |  | 2,161 | 1,636 | 5,281 | 3,833 |
Operating income (loss) |  | 653 | 790 | 3,243 | 1,585 |
Net income (loss) |  | 827 | 555 | 3,178 | 1,127 |
Depreciation and amortization |  | 116 | 111 | 332 | 313 |
Interest on long-term debt and other interest expense |  | 0 | 0 | 0 | 0 |
Provision for income taxes |  | 179 | 216 | 909 | 438 |
Assets |  | 8,589 | 5,899 | 8,589 | 5,899 |
Real Estate Services | Non-tariffed |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue |  | 1,403 | 1,353 | 4,217 | 4,088 |
Operating expense |  | 961 | 935 | 2,642 | 2,834 |
Operating income (loss) |  | 442 | 418 | 1,575 | 1,254 |
Net income (loss) |  | 310 | 304 | 1,141 | 1,284 |
Depreciation and amortization |  | 296 | 299 | 896 | 896 |
Interest on long-term debt and other interest expense |  | 0 | 0 | 0 | 0 |
Provision for income taxes |  | 105 | 95 | 361 | 445 |
Assets |  | 45,980 | 46,160 | 45,980 | 46,160 |
All Other | Non-tariffed |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue | [1] | 0 | 0 | 0 | 0 |
Operating expense | [1] | 973 | 4,418 | 4,436 | 10,441 |
Operating income (loss) | [1] | (973) | (4,418) | (4,436) | (10,441) |
Net income (loss) | [1] | (97) | (2,345) | (9,205) | (4,248) |
Depreciation and amortization | [1] | 223 | 0 | 670 | 0 |
Interest on long-term debt and other interest expense | [1] | 5,062 | 544 | 15,063 | 1,659 |
Provision for income taxes | [1] | (5,156) | (658) | (8,145) | (1,223) |
Assets | [1] | 73,367 | 414,274 | 73,367 | 414,274 |
SJW Group | Regulated |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue |  | 161,646 | 110,218 | 416,085 | 285,138 |
Operating expense |  | 119,885 | 89,924 | 323,087 | 226,073 |
Operating income (loss) |  | 41,761 | 20,294 | 92,998 | 59,065 |
Net income (loss) |  | 25,053 | 10,964 | 53,117 | 30,726 |
Depreciation and amortization |  | 21,782 | 14,712 | 64,654 | 44,159 |
Interest on long-term debt and other interest expense |  | 8,112 | 6,044 | 24,575 | 17,434 |
Provision for income taxes |  | 9,450 | 2,912 | 16,101 | 9,142 |
Assets |  | 3,131,778 | 1,556,049 | 3,131,778 | 1,556,049 |
SJW Group | Non-tariffed |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Operating revenue |  | 4,217 | 3,779 | 12,741 | 9,506 |
Operating expense |  | 4,095 | 6,989 | 12,359 | 17,108 |
Operating income (loss) |  | 122 | (3,210) | 382 | (7,602) |
Net income (loss) |  | 1,040 | (1,486) | (4,886) | (1,837) |
Depreciation and amortization |  | 635 | 410 | 1,898 | 1,209 |
Interest on long-term debt and other interest expense |  | 5,062 | 544 | 15,063 | 1,659 |
Provision for income taxes |  | (4,872) | (347) | (6,875) | (340) |
Assets |  | $ 127,936 | $ 466,333 | $ 127,936 | $ 466,333 |
[1] | * The “All Other” category for the nine months ended September 30, 2020, includes the accounts of SJW Group, SJWNE LLC and CTWS on a stand-alone basis. For the three months ended September 30, 2019, the “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis. For the three months ended September 30, 2019, Hydro Sub, Inc. had no recorded revenue or expenses and as of September 30, 2019 held no assets and incurred no liabilities. Hydro Sub. Inc. was a subsidiary created solely to facilitate the merger with CTWS and was dissolved following the completion of merger in October 2019.

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