Line Of Credit Facility, Average Borrowing Period

No definition available.

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- Definition

Line of Credit Facility, Maximum Possible Aggregate Incremental Increase

+ References

No definition available.

+ Details

Name:	ablp_LineOfCreditFacilityMaximumPossibleAggregateIncrementalIncrease
Namespace Prefix:	ablp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of financial institutions offering lines of credit.

+ References

No definition available.

+ Details

Name:	ablp_NumberOfFinancialInstitutionsOfferingLinesOfCredit
Namespace Prefix:	ablp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of financial institutions with stated limits.

+ References

No definition available.

+ Details

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Namespace Prefix:	ablp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of uncommitted lines of credit.

+ References

No definition available.

+ Details

Name:	ablp_NumberOfUncommittedLinesOfCredit
Namespace Prefix:	ablp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rates on average daily borrowings

+ References

No definition available.

+ Details

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Namespace Prefix:	ablp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityAverageOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ProceedsFromLinesOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- 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_ShortTermDebtLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_ShorttermDebtAverageOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Period Type:

- Details

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- Details

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- Details

Name:	us-gaap_ShortTermDebtTypeAxis=ablp_UncommitedLinesOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=ablp_EQHMember
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- Details

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Debt (Details)	12 Months Ended
Debt (Details)	Dec. 31, 2019 USD ($) financial_institution line_of_credit	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Nov. 04, 2019 USD ($)
Short-term Debt [Line Items]
Proceeds from EQH facility	$ 560,000,000	$ 0	$ 0
Commercial Paper
Short-term Debt [Line Items]
Weighted average interest rates on average daily borrowings	2.60%	2.00%
Short-term debt outstanding	$ 0	$ 523,200,000
Weighted average interest rate		2.70%
Short term debt, days available	317 days
Average daily borrowings	$ 438,600,000	$ 350,300,000
Credit Facility
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity	800,000,000.0
Credit facility, possible aggregate incremental limit increase	200,000,000.0
Amounts outstanding under credit facility	0	0
Proceeds from EQH facility	0	$ 0
Credit Facility \| SCB LLC
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity	$ 175,000,000.0
Number of uncommitted lines of credit \| line_of_credit	3
Number of financial institutions offering lines of credit \| financial_institution	3
Number of financial institutions with stated limits \| line_of_credit	2
Uncommitted Lines of Credit
Short-term Debt [Line Items]
Line of credit facility interest rate	1.90%	1.60%
Short-term debt outstanding	$ 0	$ 0
Average daily borrowings	1,900,000	2,700,000
Revolving Credit Facility
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity	200,000,000.0
EQH Facility
Short-term Debt [Line Items]
Amounts outstanding under credit facility	$ 560,000,000.0
Weighted average interest rates on average daily borrowings	1.60%
Long term debt, days available	57 days
Average daily borrowings	$ 358,600,000
Line of credit facility interest rate	1.60%
EQH Facility \| Revolving Credit Facility
Short-term Debt [Line Items]
Credit facility, maximum borrowing capacity				$ 900,000,000.0
Credit Facility \| Revolving Credit Facility
Short-term Debt [Line Items]
Amounts outstanding under credit facility	$ 0	25,000,000.0
Average daily borrowings	$ 23,500,000	$ 19,400,000
Line of credit facility interest rate	3.20%	2.80%
Interest rate		3.40%