| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 | Dec-31-15 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
| CASH FLOWS FROM OPERATING ACTIVITIES | | | | | | | | |
| Net loss | -39.4 | -3.9 | -88.2 | -8.0 | -145.4 | -31.5 | 46.7 | 80.8 |
| Gain on sale of mortgage servicing rights | -0.3 | -0.2 | | | | | | |
| Change in fair value of mortgage servicing rights | 0.1 | 0.1 | 22.0 | 25.8 | -3.8 | 37.9 | 24.4 | 10.9 |
| Gain on sale of mortgage loans | -20.5 | -66.1 | -35.2 | -84.0 | -88.6 | -135.7 | -309.2 | -163.0 |
| Change in fair value of mortgage loans held-for-sale | 8.8 | -3.4 | 16.0 | -15.8 | 14.8 | | | |
| Change in fair value of derivatives lending, net | 3.0 | 4.1 | 0.0 | -4.5 | 2.1 | 6.1 | -1.8 | -6.9 |
| Provision for repurchases | 2.4 | 0.1 | | | | | | |
| Origination of mortgage loans held-for-sale | -693.7 | -2,903.5 | | | | | | |
| Sale and principal reduction on mortgage loans held-for-sale | 1,000.8 | 2,828.3 | 3,381.8 | 4,217.6 | 4,103.8 | 7,019.4 | 13,026.9 | 9,252.8 |
| Change in fair value of long-term debt | -2.8 | -2.1 | -1.9 | 1.4 | | | | |
| Accretion of interest income and expense | 6.7 | 50.8 | 65.5 | 27.3 | 33.4 | 86.2 | 126.6 | 148.1 |
| Stock-based compensation | 0.7 | 0.9 | 0.7 | 0.7 | 0.9 | 2.5 | 2.1 | 1.6 |
| Impairment of ROU asset | 0.1 | | | | | | | |
| Net change in other assets | 7.2 | 2.3 | 18.3 | 8.4 | -12.2 | 0.8 | -6.6 | -5.4 |
| Net change in other liabilities | -14.4 | -5.6 | -15.9 | -12.5 | -5.0 | -17.8 | 15.4 | 8.9 |
| Net cash provided by (used in) operating activities | 249.6 | -104.5 | 633.9 | -377.5 | 201.0 | -138.0 | 65.5 | 30.7 |
| |
| CASH FLOWS FROM INVESTING ACTIVITIES | | | | | | | | |
| Net change in securitized mortgage collateral | 72.9 | 592.5 | 425.2 | 565.6 | 554.0 | 632.5 | 619.8 | 649.5 |
| Proceeds from the sale of mortgage servicing rights | 0.7 | 0.2 | | | | | | |
| Sale (purchase) of premises and equipment | 0.1 | -0.3 | -0.4 | -0.9 | -0.9 | -0.5 | -0.3 | 0.1 |
| Proceeds from the sale of trust REO | | 7.7 | 22.0 | 23.8 | 21.5 | 29.1 | 42.0 | 33.1 |
| Net cash provided by investing activities | 110.4 | 600.0 | 460.3 | 589.7 | 727.7 | 677.5 | 641.9 | 714.4 |
| |
| CASH FLOWS FROM FINANCING ACTIVITIES | | | | | | | | |
| Repayment of warehouse borrowings | -921.0 | -2,640.8 | -3,200.3 | -3,746.3 | -3,877.7 | -6,743.0 | -12,318.9 | -8,825.7 |
| Borrowings under warehouse agreements | 639.1 | 2,774.4 | 2,650.6 | 4,163.7 | 3,586.4 | 6,897.8 | 12,413.8 | 8,924.6 |
| Repayment of securitized mortgage borrowings | -78.8 | -654.1 | -518.6 | -623.0 | -610.8 | -742.4 | -787.6 | -828.2 |
| Net cash used in financing activities | -365.2 | -520.0 | -1,071.5 | -205.2 | -937.6 | -546.5 | -699.7 | -722.7 |
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| SUPPLEMENTARY INFORMATION | | | | | | | | |
| Interest paid | 11.9 | 25.7 | 50.6 | 116.8 | 123.7 | 93.8 | 77.5 | 63.3 |
| |
| NON-CASH TRANSACTIONS | | | | | | | | |
| Mortgage servicing rights retained from issuance of mortgage-backed securities and loan sales | 0.0 | 0.5 | | | | | | |