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Business Combination and Asset Purchase - Summary of Carrying Amount of Loans (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Business Acquisition [Line Items] |  |
Carrying amount, net of allowance | $ 126 | $ 2,278
Commercial [Member] |  |
Business Acquisition [Line Items] |  |
Carrying amount, net of allowance | 117 | 4,094
Consumer RE [Member] |  |
Business Acquisition [Line Items] |  |
Carrying amount, net of allowance | 73 | 231
Consumer [Member] |  |
Business Acquisition [Line Items] |  |
Carrying amount, net of allowance | $ 32 | $ 71

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- Definition The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans accounted for as debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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