| In millions, except per share items | Mar-31-23 | Mar-31-22 | Mar-31-21 | Mar-31-20 | Mar-31-19 | Mar-31-18 | Mar-31-17 | Mar-31-16 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| Revenues: | | | | | | | | |
| Revenues | 389.7 | 274.2 | 315.9 | 333.4 | 158.0 | | | |
| |
| Expenses | | | | | | | | |
| Voyage expenses | 3.6 | 4.3 | 3.4 | 3.2 | 1.7 | 2.2 | 3.0 | 12.1 |
| Charter hire expenses | 23.2 | 16.3 | 18.1 | 9.9 | 0.2 | | | |
| Vessel operating expenses | 71.5 | 74.2 | 78.2 | 71.5 | 66.9 | 64.3 | 66.1 | 47.1 |
| Depreciation and amortization | 63.4 | 66.4 | 68.5 | 66.3 | 65.2 | 65.3 | 65.1 | 42.6 |
| General and administrative expenses | 32.1 | 30.2 | 33.9 | 23.4 | 24.4 | 26.2 | 21.7 | 29.8 |
| Total expenses | 193.8 | 191.5 | 202.1 | 174.2 | 168.5 | 158.0 | 155.9 | 132.7 |
| Gain on disposal of vessels | | 7.3 | | | | | | 1.1 |
| Other income-related parties | 2.4 | 2.4 | 2.3 | 1.8 | 2.5 | | | |
| Operating income | 198.4 | 92.4 | 116.1 | 161.1 | -8.0 | 3.8 | 14.0 | 158.4 |
| |
| Other income/(expenses) | | | | | | | | |
| Interest and finance costs | -37.8 | -27.1 | -27.6 | -36.1 | -40.6 | -35.7 | -29.0 | -12.8 |
| Interest income | 3.8 | 0.3 | 0.4 | 1.5 | 1.8 | 0.4 | 0.1 | 0.1 |
| Unrealized gain on derivatives | 2.8 | 11.1 | 7.2 | -18.2 | -7.8 | 8.4 | 27.5 | -8.9 |
| Realized gain/(loss) on derivatives | 3.8 | -3.5 | -4.6 | 2.8 | | | | |
| Other gain/(loss), net | 1.5 | -1.4 | 1.0 | 0.8 | -0.1 | -0.2 | -0.3 | |
| Total other income/(expenses), net | -25.9 | -20.5 | -23.5 | -49.2 | -43.0 | -24.2 | -15.4 | -28.7 |
| Net income | 172.4 | 71.9 | 92.6 | 111.8 | -50.9 | -20.4 | -1.4 | 129.7 |
| |
| Weighted average shares outstanding Basic (in shares) | 40.0 | 40.2 | 49.7 | 53.9 | 54.5 | 54.0 | 54.1 | 56.7 |
| Weighted average shares outstanding Diluted (in shares) | 40.2 | 40.4 | 49.8 | 54.1 | 54.5 | 54.0 | 54.1 | |
| |
| Earnings per common share - basic (in dollars per share) | $4.31 | $1.79 | $1.86 | $2.08 | ($0.93) | ($0.38) | ($0.03) | $2.29 |
| Earnings per common share - diluted (in dollars per share) | $4.29 | $1.78 | $1.86 | $2.07 | ($0.93) | ($0.38) | ($0.03) | $2.29 |