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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2020
Accounting Policies [Abstract] |
Estimated Useful Lives for Various Asset | The estimated useful lives for the various asset categories are as follows:
1) Land and Land Improvements |  | Non-depreciating assets
2) Buildings |  | 25 years
3) Furniture and Fixtures |  | 5 years
4) Computer Equipment and Software |  | 5 years or term of license
5) Other Equipment |  | 5 years
6) Vehicles |  | 5 years
7) Leasehold Improvements |  | Lesser of estimated useful life of the asset (generally 15 years unless established otherwise) or the remaining term of the lease, including renewal options in the lease that are reasonably assured of exercise
Impact of ASU 2016-13 | The following table details the impact of ASU 2016-13 and the reclassification of loans for the identification of new portfolio loan segments under CECL:
| January 1, 2020
(dollars in thousands) | As Reported Under ASU 2016-13 |  | Pre-ASU 2016-13 |  | Impact of ASU 2016-13 Adoption
Assets: |  |  |  |  |  |  |  |
Loans held for investment (outstanding balance) |  |  |  |  |  |  |  |
Commercial real estate |  | $ | 2,946,319 |  |  |  | $ | 3,416,518 |  |  |  | $ | (470,199) |
Commercial and industrial |  | 1,458,541 |  |  |  | 1,720,833 |  |  |  | (262,292) |
Commercial construction |  | 345,263 |  |  |  | 375,445 |  |  |  | (30,182) |
Business banking |  | 1,092,908 |  |  |  | — |  |  |  | 1,092,908 |
Consumer real estate |  | 1,235,352 |  |  |  | 1,545,323 |  |  |  | (309,971) |
Other consumer |  | 58,769 |  |  |  | 79,033 |  |  |  | (20,264) |
Allowance for credit losses on loans |  | (89,577) |  |  |  | (62,224) |  |  |  | (27,353) |
Total loans held for investment, net |  | $ | 7,047,575 |  |  |  | $ | 7,074,928 |  |  |  | $ | (27,353) |
Net deferred tax asset |  | $ | 19,317 |  |  |  | $ | 13,206 |  |  |  | $ | 6,111 |
Liabilities: |  |  |  |  |  |  |  |
Allowance for credit losses on unfunded loan commitments |  | $ | 4,462 |  |  |  | $ | 3,113 |  |  |  | $ | 1,349 |
Equity: |  |  |  |  |  |  |  |
Retained earnings |  | $ | 738,493 |  |  |  | $ | 761,083 |  |  |  | $ | (22,590) |

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