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Mergers and Acquisitions - Consideration Transferred, Identifiable Net Assets Acquired and Goodwill Recognized (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Oct. 01, 2021 | Feb. 29, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Liabilities assumed |  |  |  |  |
Goodwill recognized |  |  | $ 471,380 | $ 57,595 | $ 166,832
Altabank |  |  |  |  |
Fair value of consideration transferred |  |  |  |  |
Fair value of Company shares issued | $ 839,853 |  |  |  |
Cash consideration | 9 |  |  |  |
Total fair value of consideration transferred | 839,862 |  |  |  |
Identifiable assets acquired |  |  |  |  |
Cash and cash equivalents | 1,622,727 |  |  |  |
Debt securities | 6,658 |  |  |  |
Loans receivable, net of ACL | 1,901,950 |  |  |  |
Core deposit Intangible | 7,021 |  |  |  |
Accrued income and other assets | 121,926 |  |  |  |
Total identifiable assets acquired | 3,660,282 |  |  |  |
Liabilities assumed |  |  |  |  |
Deposits | 3,273,819 |  |  |  |
Borrowings | 0 |  |  |  |
Accrued expenses and other liabilities | 17,981 |  |  |  |
Total liabilities assumed | 3,291,800 |  |  |  |
Total identifiable net assets | 368,482 |  |  |  |
Goodwill recognized | $ 471,380 |  |  |  |
Core deposit intangible, weighted average useful life (in years) | 10 years |  |  |  |
State Bank of Arizona |  |  |  |  |
Fair value of consideration transferred |  |  |  |  |
Fair value of Company shares issued |  | $ 112,133 |  |  |
Cash consideration |  | 13,721 |  |  |
Total fair value of consideration transferred |  | 125,854 |  |  |
Identifiable assets acquired |  |  |  |  |
Cash and cash equivalents |  | 57,434 |  |  |
Debt securities |  | 142,174 |  |  |
Loans receivable, net of ACL |  | 451,653 |  |  |
Core deposit Intangible |  | 2,593 |  |  |
Accrued income and other assets |  | 33,971 |  |  |
Total identifiable assets acquired |  | 687,825 |  |  |
Liabilities assumed |  |  |  |  |
Deposits |  | 603,289 |  |  |
Borrowings |  | 10,904 |  |  |
Accrued expenses and other liabilities |  | 5,373 |  |  |
Total liabilities assumed |  | 619,566 |  |  |
Total identifiable net assets |  | 68,259 |  |  |
Goodwill recognized |  | $ 57,595 |  |  |
Core deposit intangible, weighted average useful life (in years) |  | 10 years |  |  |

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