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Revenue | 3 Months Ended
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Mar. 31, 2018
Revenue from Contract with Customer [Abstract] |
Revenue | Revenue Our revenue is comprised primarily of interest income, service charges and fees, gains on the sale of loans and AFS securities, earnings on corporate owned life insurance policies, and other noninterest income. Other noninterest income is typically service and performance driven in nature and comprised primarily of trust and brokerage advisory fees. We recognize revenue in accordance with GAAP as outlined in ASC 606, Revenue From Contracts with Customers. Revenue is recognized when our performance obligation has been satisfied according to our contractual obligation. We record receivables when revenue is unpaid and collectability is reasonably assured. Accounts receivable balances primarily represent amounts due from customers for which revenue has been recognized. Accounts receivable balances are recorded in the consolidated balance sheets in accrued interest receivable and other assets. For the three month periods ended March 31, 2018 and 2017, we satisfied our performance obligations pursuant to contracts with customers. As a result, we have not recorded contract assets or liabilities. We estimate no returns or allowances for the three month periods ended March 31, 2018 and 2017. Our contracts with customers define our performance obligations with clearly established pricing which did not require us to allocate or disaggregate revenue by performance obligation. A summary of revenue recognized for each major category of contracts with customers, subject to ASC 606, is as follows for the:
| Three Months Ended March 31
| 2018 |  | 2017
Debit card income | $ | 588 |  |  | $ | 530 |
Trust service fees | 502 |  |  | 411 |
Brokerage advisory fees | 156 |  |  | 160 |
Service charges and fees related to deposit accounts | 85 |  |  | 85 |
Total | $ | 1,331 |  |  | $ | 1,186 |
A large portion of our revenue consists of interest income which is not subject to the requirements set forth in ASU 2014-09. This recently adopted guidance required us to review our other noninterest revenue sources within the scope of the guidance to ensure appropriate recognition of revenue from contracts with customers. This review process did not identify significant changes related to revenue recognition. As such, we did not record or disclose transactions related to the adoption of this guidance.

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