Name:	bpfh_TimeDepositMaturitiesAfterOneButWithinThreeYears
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Time Deposit Maturities, After Three but Within Five Years - Amount of time deposits maturing after three, but within five fiscal years, following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

No definition available.

Name:	bpfh_TimeDepositMaturitiesAfterThreeButWithinFiveYears
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Time Deposit Maturities, Less than Three Months - Amount of time deposits maturing in the next three months following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

No definition available.

Name:	bpfh_TimeDepositMaturitiesLessThanThreeMonths
Namespace Prefix:	bpfh_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Time Deposit Maturities, Six to Twelve Months - Amount of time deposits maturing within six to twelve months following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

No definition available.

Name:	bpfh_TimeDepositMaturitiesSixToTwelveMonths
Namespace Prefix:	bpfh_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Time Deposit Maturities, Three to Six Months - Amount of time deposits maturing within three to six months following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

No definition available.

Name:	bpfh_TimeDepositMaturitiesThreeToSixMonths
Namespace Prefix:	bpfh_
Data Type:	xbrli:monetaryItemType
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Time Deposits [Line Items]

No definition available.

Name:	bpfh_TimeDepositsLineItems
Namespace Prefix:	bpfh_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of time deposits maturing after the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Name:	us-gaap_TimeDepositMaturitiesAfterYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of time deposit liabilities, including certificates of deposit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E