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Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Includes allowance for purchased credit-impaired loans.No definition available.false2Allowance for loan losses, beginning of period3false 4ub_ProvisionForLoanLeaseAndOtherLossesByLoanPortfolioub_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-3000000-3falsefalsefalse2truefalsefalse-13000000-13falsefalsefalse3truefalsefalse-6000000-6falsefalsefalse4truefalsefalse-12000000-12falsefalsefalse5truefalsefalse-3000000-3falsefalsefalse6truefalsefalse-38000000-38falsefalsefalse7truefalsefalse6500000065falsefalsefalse8truefalsefalse-41000000-41falsefalsefalse9falsefalsefalse00falsefalsefalse10truefalsefalse1400000014falsefalsefalse11truefalsefalse10000001falsefalsefalse12truefalsefalse2600000026falsefalsefalse13falsefalsefalse00falsefalsefalse14falsefalsefalse00falsefalsefalse15falsefalsefalse00falsefalsefalse16falsefalsefalse00falsefalsefalse17truefalsefalse1100000011falsefalsefalse18truefalsefalse-72000000-72falsefalsefalse19truefalsefalse30000003falsefalsefalse20falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value by loan portfolio.No definition available.false2(Reversal of) provision for loan losses4false 4us-gaap_AllowanceForLoanAndLeaseLossesProvisionForLossGrossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse-1000000-1falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse-3000000-3falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalse14truefalsefalse-1000000-1falsefalsefalse15falsefalsefalse00falsefalsefalse16truefalsefalse-3000000-3falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2(Reversal of) provision for FDIC covered loan losses not subject to FDIC indemnification5false 4us-gaap_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecreaseus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-2000000-2falsefalsefalse2truefalsefalse-3000000-3falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse-9000000-9falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13truefalsefalse-2000000-2falsefalsefalse14truefalsefalse-3000000-3falsefalsefalse15falsefalsefalse00falsefalsefalse16truefalsefalse-9000000-9falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReflects the sum for the period of the additions and reductions to the loan loss reserve, which when added to the opening balance of the reserve will agree to the ending balance in the reserve.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Decrease in allowance covered by FDIC indemnification6false 4us-gaap_AllowanceForLoanAndLeaseLossesWriteOffsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-20000000-20falsefalsefalse2truefalsefalse-44000000-44falsefalsefalse3truefalsefalse-39000000-39falsefalsefalse4truefalsefalse-107000000-107falsefalsefalse5truefalsefalse-12000000-12falsefalsefalse6truefalsefalse-26000000-26falsefalsefalse7truefalsefalse-15000000-15falsefalsefalse8truefalsefalse-66000000-66falsefalsefalse9truefalsefalse-8000000-8falsefalsefalse10truefalsefalse-16000000-16falsefalsefalse11truefalsefalse-21000000-21falsefalsefalse12truefalsefalse-39000000-39falsefalsefalse13falsefalsefalse00falsefalsefalse14truefalsefalse-2000000-2falsefalsefalse15truefalsefalse-3000000-3falsefalsefalse16truefalsefalse-2000000-2falsefalsefalse17falsefalsefalse00falsefalsefalse18falsefalsefalse00falsefalsefalse19falsefalsefalse00falsefalsefalse20falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 114 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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