In millions, except per share items | Jun-30-23 | Mar-31-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 |
| 10-Q | 10-Q | 8-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
Revenues | | | | | | | | |
Total revenues | 20.5 | 20.8 | 0.0 | 20.1 | 19.7 | 19.1 | 19.1 | 19.3 |
Total revenues growth | 4.4% | 8.8% | -99.9% | 4.2% | -0.2% | -6.4% | -10.4% | -10.0% |
Operating expenses | | | | | | | | |
Operations and maintenance | 7.1 | 7.3 | | | 6.2 | 5.6 | | |
General and administrative | 1.6 | 1.2 | 0.0 | 0.9 | 0.9 | 1.2 | | 0.9 |
Depreciation and amortization | 0.8 | 0.8 | | 1.2 | 0.8 | 0.9 | | 1.1 |
Total operating expenses | 9.5 | 9.3 | 0.0 | 8.4 | 7.9 | 7.6 | 8.1 | 7.1 |
Operating income | 11.0 | 11.5 | 0.0 | 11.6 | 11.7 | 11.5 | -3.8 | 12.1 |
Operating margin | 53.6% | 55.2% | 20.6% | 58.0% | 59.8% | 60.0% | -20.0% | 62.9% |
Investment Income, Interest | 0.2 | | | | | | | |
Interest expense | -1.9 | -1.8 | | -1.5 | -1.4 | -1.2 | | -2.8 |
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest | 9.3 | 9.7 | 0.0 | 10.1 | 10.4 | 10.2 | 9.7 | 9.3 |
Income tax expense | -0.3 | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 |
Tax rate | 3.1% | | 650.0% | | 0.4% | 0.4% | | |
Income from equity method investee | 0.3 | 0.1 | 0.2 | 0.1 | 0.2 | 0.2 | | 0.2 |
Net income | 9.3 | 9.9 | 9.6 | 10.2 | 10.5 | 10.4 | 9.9 | 9.4 |
|
Net income attributable to partners' ownership interests | | | | | | | | |
General partner | 0.2 | 0.2 | | 0.2 | 0.2 | 0.2 | | 0.2 |
Limited partners - common unitholders | 9.2 | 9.7 | | 10.0 | 10.3 | 10.1 | | 9.2 |
|
Earnings per limited partner unit (basic and diluted) | | | | | | | | |
Common units, basic (in dollars per share) | | | | | | | | |
Common units, diluted (in dollars per share) | | | | | | | | |
Weighted average limited partner units outstanding (basic and diluted) | | | | | | | | |
Common units, basic (in shares) | | | | | | | | |
Common units, diluted (in shares) | | | | | | | | |
Share-based Payment Arrangement, Expense | | | | | | | | |