| In millions, except per share items | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 | Mar-31-21 | Dec-31-20 | Sep-30-20 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Cash flows from operating activities: | | | | | | | | |
| Net income (loss) | | | | | | | -594.7 | |
| Adjustments to reconcile net income (loss) to net cash from operating activities: | | | | | | | | |
| Depreciation and amortization | 59.0 | 59.1 | 59.2 | 59.3 | 59.2 | 61.0 | 59.8 | 60.1 |
| Provision for expected credit losses | -0.2 | -0.5 | -0.3 | 0.2 | | -2.6 | | |
| Amortization of debt issuance costs | 1.8 | 1.8 | 2.9 | 2.3 | 2.3 | 2.3 | 2.3 | 2.2 |
| Unit-based compensation expense | 3.0 | 3.7 | 3.6 | 3.5 | 4.3 | 4.2 | 4.3 | 1.3 |
| Deferred income tax expense (benefit) | 0.0 | -0.2 | 0.1 | 0.0 | 0.0 | -0.1 | 0.2 | 0.1 |
| Loss (gain) on disposition of assets | 1.0 | -0.2 | -0.3 | 0.0 | -1.1 | -1.3 | 0.3 | 1.7 |
| Impairment of compression equipment | | 0.4 | 0.2 | | 2.4 | 2.6 | 2.5 | 1.7 |
| Impairment of goodwill | | | | | | | | |
| Changes in assets and liabilities: | | | | | | | | |
| Accounts receivable and related-party receivables, net | -3.5 | -1.1 | -4.7 | 3.2 | 4.4 | -2.8 | 9.1 | 1.3 |
| Inventories | -6.0 | -5.2 | -2.4 | -3.7 | -3.2 | -3.3 | 0.4 | -1.1 |
| Prepaid expenses and other current assets | -2.1 | -0.9 | 0.0 | -2.0 | -1.2 | -0.5 | 0.5 | 0.9 |
| Other assets | 0.7 | 0.9 | 0.8 | 0.9 | 1.1 | 0.7 | 0.7 | 0.8 |
| Accounts payable | 0.8 | -2.2 | 5.6 | 1.0 | 1.2 | 1.3 | 0.4 | -3.9 |
| Accrued liabilities and deferred revenue | 30.6 | -23.8 | 13.3 | -18.5 | 27.5 | -23.7 | 20.4 | -31.2 |
| Other liabilities | | | | | | | 0.0 | |
| Net cash provided by operating activities | 94.2 | 35.1 | 81.1 | 45.3 | 99.5 | 39.6 | 97.5 | 48.2 |
| |
| Cash flows from investing activities: | | | | | | | | |
| Capital expenditures, net | -23.6 | -20.2 | -15.8 | -14.0 | -9.3 | -6.2 | -11.2 | -30.5 |
| Proceeds from disposition of property and equipment | 0.3 | 0.5 | 0.3 | 0.6 | 3.2 | 0.4 | 0.3 | 0.1 |
| Proceeds from insurance recovery | 0.1 | 0.0 | | | | 1.6 | | |
| Net cash used in investing activities | -23.2 | -19.7 | -15.5 | -13.4 | -6.1 | -4.2 | -10.9 | -30.4 |
| |
| Cash flows from financing activities: | | | | | | | | |
| Proceeds from revolving credit facility | 167.9 | 215.0 | 169.2 | 197.8 | 140.2 | 190.5 | 148.7 | 216.5 |
| Payments on revolving credit facility | -174.8 | -165.8 | -158.5 | -165.6 | -169.4 | -161.6 | -171.8 | -167.4 |
| Cash paid related to net settlement of unit-based awards | | | -3.2 | | | | -1.1 | |
| Cash distributions | | | | | | | | |
| Deferred financing costs | -0.1 | -0.4 | -9.8 | 0.0 | -0.1 | | -0.1 | -3.5 |
| Other | -0.1 | -0.1 | -0.2 | -0.1 | -0.1 | -0.1 | -0.1 | -0.1 |
| Net cash used in financing activities | -71.1 | -15.3 | -65.8 | -31.7 | -93.5 | -35.3 | -86.6 | -17.8 |
| Increase (decrease) in cash and cash equivalents | | | 0.0 | | | | 0.0 | |
| |
| Supplemental cash flow information: | | | | | | | | |
| Cash paid for interest, net of capitalized amounts | 5.5 | 54.7 | 4.8 | 55.3 | 5.0 | 55.4 | 4.8 | 55.1 |
| Cash paid for income taxes | | | | | | | | |
| Supplemental non-cash transactions: | | | | | | | | |
| Non-cash distributions to certain common unitholders (DRIP) | 0.5 | 0.5 | 0.5 | 0.4 | 0.4 | 0.5 | 0.5 | 0.5 |
| Transfers from inventories to property and equipment | 5.6 | 1.1 | 1.0 | 3.1 | 3.5 | 3.1 | 4.0 | 3.0 |
| Changes in capital expenditures included in accounts payable and accrued liabilities | 9.1 | 1.9 | | | 0.3 | -0.8 | -8.6 | |
| Changes in financing costs included in accounts payable and accrued liabilities | -0.1 | -0.1 | | | 0.0 | 0.1 | | |
| Exercise and conversion of warrants into common units | 5.2 | | | | | | | |