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LOANS AND LEASES - Commercial Real Estate Loans (Detail) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items] |  |
Document Period End Date | Jun. 30, 2019 |
Commercial construction, acquisition and development loans | $ 1,196 | $ 1,152
Credit Concentration Risk [Member] | Commercial Construction Loans [Member] |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Percent of total loans and leases | 5.30% | 5.20%
Loan Portfolio Diversification Risk [Member] | Commercial Real Estate Loans [Member] | Owner-Occupied [Member] |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Percent of total loans and leases | 31.70% | 35.10%
Loan Portfolio Diversification Risk [Member] | Commercial Real Estate Loans [Member] | Non-Owner-Occupied [Member] |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Percent of total loans and leases | 68.30% | 64.90%

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