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Loans Held for Investment - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | $ 59.5 |  |  |
Provision charged (credited) to operating expense | 82.7 | $ (14.6) | $ 56.9 |
Less loans charged-off | (45.0) | (16.6) | (20.9) |
Recoveries Collected | 14.9 | 9.3 | 6.7 |
Accounts Receivable, Allowance for Credit Loss | 220.1 | 122.3 | 144.3 | $ 73.0
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 68.4 | (14.7) | 55.5 |
Great Western Bank |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) | 68.3 |  |  |
Non Owner Occupied Loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 17.2 |  |  |
Provision charged (credited) to operating expense | (4.2) | (8.3) | 11.7 |
Less loans charged-off | (3.5) | 0.0 | 0.0 |
Recoveries Collected | 0.4 | 0.1 | 0.1 |
Accounts Receivable, Allowance for Credit Loss | 27.2 | 17.3 | 25.5 | 8.8
Commercial Real Estate Owner Occupied |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 9.5 |  |  |
Provision charged (credited) to operating expense | (2.7) | (2.7) | 5.0 |
Less loans charged-off | (2.5) | (2.3) | (0.4) |
Recoveries Collected | 1.9 | 0.0 | 0.2 |
Accounts Receivable, Allowance for Credit Loss | 19.5 | 13.3 | 18.3 | 10.0
Commercial Real Estate Multifamily |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 10.9 |  |  |
Provision charged (credited) to operating expense | 8.7 | 2.3 | 3.4 |
Less loans charged-off | (5.7) | 0.0 | 0.0 |
Recoveries Collected | 0.7 | 0.0 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | 27.9 | 13.3 | 11.0 | 0.7
Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 37.6 |  |  |
Provision charged (credited) to operating expense | 1.8 | (8.7) | 20.1 |
Less loans charged-off | (11.7) | (2.3) | (0.4) |
Recoveries Collected | 3.0 | 0.1 | 0.3 |
Accounts Receivable, Allowance for Credit Loss | 74.6 | 43.9 | 54.8 | 19.5
Land Acquisition And Development Construction Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 3.4 |  |  |
Provision charged (credited) to operating expense | (0.4) | (0.1) | (0.4) |
Less loans charged-off | (2.6) | (1.2) | (0.5) |
Recoveries Collected | 0.4 | 0.5 | 0.4 |
Accounts Receivable, Allowance for Credit Loss | 1.3 | 0.5 | 1.3 | 1.9
Residential Real Estate Construction Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 1.1 | 0.9 | 1.0 |
Less loans charged-off | 0.0 | (0.1) | 0.0 |
Recoveries Collected | 0.1 | 0.0 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | 3.6 | 2.4 | 1.6 | 1.5
Commercial Real Estate Construction [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.2 |  |  |
Provision charged (credited) to operating expense | 31.6 | (1.3) | 3.3 |
Less loans charged-off | (6.6) | (0.1) | 0.0 |
Recoveries Collected | 0.0 | 0.1 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | 31.2 | 6.0 | 7.3 | 2.7
Construction Loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 3.6 |  |  |
Provision charged (credited) to operating expense | 32.3 | (0.5) | 3.9 |
Less loans charged-off | (9.2) | (1.4) | (0.5) |
Recoveries Collected | 0.5 | 0.6 | 0.4 |
Accounts Receivable, Allowance for Credit Loss | 36.1 | 8.9 | 10.2 | 6.1
Residential Real Estate 1-4 Family |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.1 |  |  |
Provision charged (credited) to operating expense | 6.9 | 2.0 | (1.1) |
Less loans charged-off | (0.2) | 0.0 | 0.0 |
Recoveries Collected | 0.3 | 0.0 | 0.1 |
Accounts Receivable, Allowance for Credit Loss | 20.5 | 13.4 | 11.4 | 1.8
Home equity line of credit |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 0.0 |  |  |
Less loans charged-off | (0.1) |  |  |
Recoveries Collected | 0.5 |  |  |
Accounts Receivable, Allowance for Credit Loss | 1.6 | 1.2 |  |
Residential Real Estate |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.1 |  |  |
Provision charged (credited) to operating expense | 6.9 | 1.6 | (1.5) |
Less loans charged-off | (0.3) | (0.1) | 0.0 |
Recoveries Collected | 0.8 | 0.3 | 0.4 |
Accounts Receivable, Allowance for Credit Loss | 22.1 | 14.6 | 12.8 | 2.8
Agricultural Real Estate Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 2.3 |  |  |
Provision charged (credited) to operating expense | 1.5 | (0.1) | 0.4 |
Less loans charged-off | (0.2) | (0.7) | 0.0 |
Recoveries Collected | 0.4 | 0.0 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | 5.9 | 1.9 | 2.7 | 0.5
Real Estate Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 43.6 |  |  |
Provision charged (credited) to operating expense | 42.5 | (7.7) | 22.9 |
Less loans charged-off | (21.4) | (4.5) | (0.9) |
Recoveries Collected | 4.7 | 1.0 | 1.1 |
Accounts Receivable, Allowance for Credit Loss | 138.7 | 69.3 | 80.5 | 28.9
Indirect consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 2.7 | (1.4) | 5.4 |
Less loans charged-off | (4.0) | (3.5) | (4.1) |
Recoveries Collected | 2.3 | 2.5 | 2.1 |
Accounts Receivable, Allowance for Credit Loss | 15.3 | 14.3 | 16.7 | 4.5
Other consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 2.2 | 1.7 | 1.6 |
Less loans charged-off | (3.7) | (2.9) | (3.9) |
Recoveries Collected | 2.1 | 1.2 | 1.0 |
Accounts Receivable, Allowance for Credit Loss | 5.2 | 4.6 | 4.6 | 2.9
Credit card consumer |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 2.4 | 0.6 | 1.8 |
Less loans charged-off | (2.4) | (1.8) | (2.8) |
Recoveries Collected | 0.6 | 0.8 | 0.8 |
Accounts Receivable, Allowance for Credit Loss | 2.8 | 2.2 | 2.6 | 2.5
Total consumer loans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 7.3 | 0.9 | 8.8 |
Less loans charged-off | (10.1) | (8.2) | (10.8) |
Recoveries Collected | 5.0 | 4.5 | 3.9 |
Accounts Receivable, Allowance for Credit Loss | 23.3 | 21.1 | 23.9 | 9.9
Commercial and Floor Plans |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 11.2 |  |  |
Provision charged (credited) to operating expense | 15.1 | (7.3) | 20.4 |
Less loans charged-off | (6.6) | (3.0) | (8.0) |
Recoveries Collected | 2.2 | 3.2 | 1.4 |
Accounts Receivable, Allowance for Credit Loss | 49.0 | 27.1 | 34.2 | 25.5
Commercial Purpose Secured by 1-4 Family |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.2 |  |  |
Provision charged (credited) to operating expense | 1.2 | (0.5) | 2.5 |
Less loans charged-off | (0.2) | (0.3) | (0.1) |
Recoveries Collected | 0.1 | 0.5 | 0.2 |
Accounts Receivable, Allowance for Credit Loss | 5.7 | 4.4 | 4.7 | 5.9
Commercial Borrower |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 0.0 |  |  |
Provision charged (credited) to operating expense | 1.4 | 0.1 | 1.1 |
Less loans charged-off | (1.3) | (0.4) | (1.0) |
Recoveries Collected | 0.0 | 0.1 | 0.1 |
Accounts Receivable, Allowance for Credit Loss | 0.2 | 0.1 | 0.3 | 1.2
Commercial Portfolio Segment [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 11.4 |  |  |
Provision charged (credited) to operating expense | 17.7 | (7.7) | 24.0 |
Less loans charged-off | (8.1) | (3.7) | (9.1) |
Recoveries Collected | 2.3 | 3.8 | 1.7 |
Accounts Receivable, Allowance for Credit Loss | 54.9 | 31.6 | 39.2 | 32.6
Agricultural Financing Receivable [Member] |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 4.5 |  |  |
Provision charged (credited) to operating expense | 0.9 | (0.2) | (0.2) |
Less loans charged-off | (5.4) | (0.2) | (0.1) |
Recoveries Collected | 2.9 | 0.0 | 0.0 |
Accounts Receivable, Allowance for Credit Loss | $ 3.2 | 0.3 | 0.7 | 1.6
Home Equity Loan |  |  |  |
Financing Receivable, Allowance for Credit Losses |  |  |  |
Provision charged (credited) to operating expense |  | (0.4) | (0.4) |
Less loans charged-off |  | (0.1) | 0.0 |
Recoveries Collected |  | 0.3 | 0.3 |
Accounts Receivable, Allowance for Credit Loss |  | $ 1.2 | $ 1.4 | $ 1.0

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