| In millions, except per share items | Jun-30-23 | Dec-31-22 | Sep-30-22 | Jun-30-22 | Mar-31-22 | Dec-31-21 | Sep-30-21 | Jun-30-21 |
| | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q | 10-Q |
| Cash flows from operating activities: | | | | | | | | |
| Net increase (decrease) in net assets resulting from operations | | -1.3 | 5.9 | -4.0 | | | | |
| Adjustments to reconcile net increase (decrease) in net assets resulting from operations to net cash from (used in) operating activities: | | | | | | | | |
| Purchases of portfolio investments | -11.7 | | | -495.2 | | | | |
| Net cash acquired from mergers (cash consideration paid) (See Note 9) | | | | 101.9 | | | | |
| Transaction costs from mergers (See Note 9) | | 8.0 | -8.0 | -6.8 | | | | |
| Loan origination and other fees received | | 4.2 | 16.0 | 11.5 | | | | |
| Net realized (gain) loss on investments | | 0.5 | 10.5 | 7.7 | | -2.6 | | |
| Net realized (gain) loss on foreign currency transactions | 2.3 | -17.2 | -6.7 | 4.0 | | | | |
| Net unrealized (appreciation) depreciation on investments | -53.7 | | | 62.8 | | | | |
| Net unrealized (appreciation) depreciation of CSAs | -2.0 | -3.6 | 10.3 | 13.8 | | -1.8 | | |
| Net unrealized (appreciation) depreciation on foreign currency transactions | 0.6 | 44.7 | -52.6 | -35.3 | | -17.3 | | |
| Payment-in-kind interest / dividends | | -12.3 | | -5.3 | | -10.8 | | |
| Amortization of deferred financing fees | | -2.2 | -6.3 | -3.8 | | -7.8 | | |
| Accretion of loan origination and other fees | | -2.2 | -6.3 | -3.8 | | -7.8 | | |
| Amortization / accretion of purchased loan premium / discount | | -0.8 | -1.6 | -1.2 | | -4.6 | | |
| Payments for derivative contracts | | -0.6 | -5.0 | -2.9 | | -2.4 | | |
| Proceeds from derivative contracts | | 15.3 | 15.5 | 2.9 | | | | |
| Changes in operating assets and liabilities: | | | | | | | | |
| Interest and fees receivable | | 21.7 | -36.3 | -50.5 | | -14.5 | | |
| Prepaid expenses and other assets | | 0.1 | -3.3 | -2.6 | | -2.2 | | |
| Accounts payable and accrued liabilities | | -9.8 | 2.0 | -0.2 | | | | |
| Interest payable | | -2.1 | 4.0 | 1.0 | | | | |
| Net cash provided by (used in) operating activities | 0.9 | -23.4 | 109.7 | -12.7 | | -396.6 | | |
| |
| Cash flows from financing activities: | | | | | | | | |
| Borrowings under credit facilities | | 60.0 | 184.7 | 184.7 | | | | |
| Financing fees paid | | 0.0 | -1.9 | -1.8 | | -7.3 | | |
| Purchases of shares in repurchase plan | | -8.5 | -23.6 | -15.1 | | | | |
| Cash dividends / distributions paid | | -26.0 | -67.7 | -41.5 | | -53.6 | | |
| Net cash provided by (used in) financing activities | | 25.5 | -56.6 | 126.2 | | | | |
| Net increase (decrease) in cash and foreign currencies | | 2.1 | 53.1 | 113.5 | | -8.2 | | |
| |
| Supplemental Information: | | | | | | | | |
| Cash paid for interest | | 17.6 | 33.0 | 21.8 | | | | |
| Supplemental non-cash information | | | | | | | | |
| Acquisitions (See Note 9): | | | | | | | | |
| Fair value of net assets acquired, net of cash | | -435.8 | | -435.8 | | | | |
| Transaction costs | | | | | | | | |
| Common stock issued in acquisition of net assets | | | 499.4 | 499.4 | | | | |
| Credit support agreement (See Note 2) | | | -44.4 | -44.4 | | | | |
| Deemed contribution - from Adviser | | 0.0 | 27.7 | 27.7 | | | | |
| Deemed contributions - CSA | | | 44.4 | 44.4 | | | | |