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Business Combinations - Narrative (Details) |  | 3 Months Ended | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 01, 2025 USD ($) banking_office $ / shares shares | Jun. 30, 2025 USD ($) | Jun. 30, 2025 USD ($) | Mar. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Jun. 30, 2024 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Business Combination [Line Items] |  |  |  |  |  |  |  |
Assets |  | $ 8,280,142,000 | $ 8,280,142,000 |  | $ 6,295,910,000 |  |  |
Loans |  | 5,663,918,000 | 5,663,918,000 |  | 4,080,466,000 |  |  |
Deposits |  | 6,954,686,000 | 6,954,686,000 |  | 5,329,075,000 |  |  |
Goodwill |  | 377,976,000 | 377,976,000 |  | 179,025,000 |  |  |
Acquired loan balance |  | 1,466,891,000 | 1,466,891,000 |  |  |  |  |
Allowance for credit losses |  | 75,510,000 | 75,510,000 | $ 75,158,000 | $ 44,436,000 | $ 43,946,000 | $ 43,754,000 | $ 43,765,000
Heartland BancCorp |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Number of banking offices | banking_office | 20 |  |  |  |  |  |  |
Assets | $ 1,940,000,000 |  |  |  |  |  |  |
Loans | 1,580,000,000 |  |  |  |  |  |  |
Deposits | 1,730,000,000 |  |  |  |  |  |  |
Direct acquisition costs | 23,060,000 |  |  |  |  |  |  |
Goodwill | 198,951,000 |  |  |  |  |  |  |
Intangible assets | 40,065,000 |  |  |  |  |  |  |
Goodwill deductible for tax purposes | 0 |  |  |  |  |  |  |
Cash paid for acquisition | 23,102,000 |  |  |  |  |  |  |
Fair value of non-impaired loans and customers receivables acquired | 1,503,973,000 |  |  |  |  |  |  |
Acquired loan balance | 1,569,631,000 |  |  |  |  |  |  |
Non-recurring merger costs excluded from pro forma information |  | 928,000 | 6,860,000 |  |  |  |  |
Allowance for credit losses |  | $ 16,200,000 | $ 16,200,000 |  |  |  |  |
Heartland BancCorp | Synergies and cost savings |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Goodwill | 198,951,000 |  |  |  |  |  |  |
Heartland BancCorp | PCD Loans |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Fair value of non-impaired loans and customers receivables acquired | 78,478,000 |  |  |  |  |  |  |
Acquired loan balance | 100,836,000 |  |  |  |  |  |  |
Estimated contractual cash flows of purchased financial asset with credit deterioration | $ 15,908,000 |  |  |  |  |  |  |
Heartland BancCorp | Common stock |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Share price (in dollars per share) | $ / shares | $ 3.90 |  |  |  |  |  |  |
Shares issued for acquisition (in shares) | shares | 7,742,723 |  |  |  |  |  |  |
Heartland BancCorp | Core Deposits |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Intangible assets | $ 40,065,000 |  |  |  |  |  |  |
Weighted average useful live of acquired intangibles (in years) | 8 years |  |  |  |  |  |  |

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