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SEGMENT AND GEOGRAPHICAL INFORMATION - Revenue and Assets by Segment (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) segment | Sep. 30, 2024 USD ($) | Mar. 31, 2025 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |
Number of reportable segments | segment |  |  | 3 |  |
Revenues | $ 659,452 | $ 574,957 | $ 1,264,801 | $ 1,088,566 |
Employee compensation and benefits | 405,562 | 353,599 | 777,851 | 669,468 |
Segment profit | 222,839 | 189,963 | 410,593 | 347,175 |
Corporate expenses | 508,111 | 444,288 | 1,023,660 | 863,157 |
Other (income) expense, net | (8,712) | (5,419) | (16,962) | (10,553) |
Income before provision for income taxes | 160,053 | 136,088 | 258,103 | 235,962 |
Total assets | 3,793,365 |  | 3,793,365 |  | $ 3,819,708
Operating Segments |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Total assets | 1,731,217 |  | 1,731,217 |  | 1,698,951
Operating Segments | Corporate Finance |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Revenues | 438,661 | 364,028 | 837,180 | 692,445 |
Employee compensation and benefits | 246,502 | 214,257 | 466,006 | 395,774 |
Non-compensation expense by segment | 44,829 | 40,116 | 97,063 | 86,594 |
Segment profit | 147,330 | 109,655 | 274,111 | 210,077 |
Total assets | 1,322,976 |  | 1,322,976 |  | 1,312,291
Operating Segments | Financial Restructuring |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Revenues | 133,803 | 131,568 | 262,019 | 248,990 |
Employee compensation and benefits | 72,913 | 59,350 | 144,632 | 126,444 |
Non-compensation expense by segment | 10,790 | 11,299 | 23,643 | 22,478 |
Segment profit | 50,100 | 60,919 | 93,744 | 100,068 |
Total assets | 186,851 |  | 186,851 |  | 179,498
Operating Segments | Financial Advisory Services |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Revenues | 86,988 | 79,361 | 165,602 | 147,131 |
Employee compensation and benefits | 46,759 | 47,316 | 92,693 | 85,366 |
Non-compensation expense by segment | 14,820 | 12,656 | 30,171 | 24,735 |
Segment profit | 25,409 | 19,389 | 42,738 | 37,030 |
Total assets | 221,390 |  | 221,390 |  | 207,162
Segment Reporting, Reconciling Item, Corporate Nonsegment |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Corporate expenses | 71,498 | 59,294 | 169,452 | 121,766 |
Total assets | 2,062,148 |  | 2,062,148 |  | $ 2,120,757
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Other (income) expense, net | $ (8,712) | $ (5,419) | $ (16,962) | $ (10,553) |

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