XML 96 R80.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Loan and Lease Receivables - Estimated Fair Value of Impaired Loans Acquired at Acquisition (Details) - Acquired Impaired Loans - USD ($) | Dec. 31, 2017 | Dec. 31, 2016 | Oct. 14, 2016
--- | --- | --- | ---
Accounts Notes And Loans Receivable [Line Items] |  |  |
Undiscounted contractual cash flows |  |  | $ 66,488,000
Undiscounted cash flows not expected to be collected (non-accretable difference) |  |  | (19,918,000)
Undiscounted cash flows expected to be collected |  |  | 46,570,000
Accretable yield at acquisition |  |  | (6,916,000)
Estimated fair value of impaired loans acquired at acquisition | $ 0 | $ 0 | $ 39,654,000

X
- Definition The amount of certain loans acquired in transfer accounted for as debt securities, accretable yield at acquisition. + References No definition available. + Details
Name: | by_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldAcquisition
Namespace Prefix: | by_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cash flows not expected to be collected at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality. + References No definition available. + Details
Name: | by_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsNotExpectedToBeCollectedAtAcquisition
Namespace Prefix: | by_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
Name: | us-gaap_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodAtAcquisitionAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cash flows expected to be collected at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
Name: | us-gaap_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsExpectedToBeCollectedAtAcquisition
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of contractually required payments receivable at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
Name: | us-gaap_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAcquiredDuringPeriodContractuallyRequiredPaymentsReceivableAtAcquisition
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=by_AcquiredImpairedLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |