Represents the interest rate reset period for notes payable.

No definition available.

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- Definition

Represents the interest rate reset period for notes receivable.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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Period Type:	duration

- Definition

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1-5)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Available-for-Sale Securities
-URI http://asc.fasb.org/extlink&oid=6505594

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Subparagraph a, f, g
-Article 7

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

+ References

No definition available.

+ Details

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

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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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

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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Name:	us-gaap_LongtermDebtTypeAxis=all_SurplusNotesDue2029At6.74PercentMember
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Related Party Transactions (Details 2) - USD ($) $ in Thousands				12 Months Ended
	Dec. 18, 2009	Jun. 30, 2008	Jun. 30, 2006	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 01, 2015	Aug. 31, 2011	Apr. 30, 2011	Mar. 31, 2011	Nov. 17, 2008	Aug. 01, 2005
Related Party Transactions
Notes due to related parties				$ 275,000	$ 275,000
Net investment income on recourse notes				1,876,000	2,151,000	$ 2,593,000
Kennett
Related Party Transactions
Net investment income on recourse notes				15,000	15,000	15,000
Interest expense				16,000	16,000	16,000
Kennett \| 4.86% Recourse Note due July 1, 2035
Related Party Transactions
Notes payable interest rate (as a percent)								3.04%					4.86%
Kennett \| 5.98% Recourse Note due June 1, 2036
Related Party Transactions
Notes payable interest rate (as a percent)			5.98%
Recourse notes receivable interest rate reset period			10 years
Basis spread over reference rate for reset of notes receivable interest rate (as a percent)			0.94%
Kennett \| 5.73% Recourse Note due June 1, 2038
Related Party Transactions
Notes payable interest rate (as a percent)		5.73%
Recourse notes receivable interest rate reset period		10 years
Basis spread over reference rate for reset of notes receivable interest rate (as a percent)		1.89%
Kennett \| 5.19% Recourse Note due Dec 1, 2029
Related Party Transactions
Notes payable interest rate (as a percent)	5.19%
Recourse notes receivable interest rate reset period	10 years
Basis spread over reference rate for reset of notes receivable interest rate (as a percent)	1.70%
Kennett \| 6.74% Surplus Note, due 2029
Related Party Transactions
Notes due to related parties				$ 25,000	$ 25,000
Notes payable interest rate (as a percent)				6.74%	6.74%
Kennett \| 5.06% Surplus Note, due 2035
Related Party Transactions
Notes due to related parties				$ 100,000	$ 100,000
Notes payable interest rate (as a percent)				3.24%	3.24%
Kennett \| 6.18% Surplus Note, due 2036
Related Party Transactions
Notes due to related parties				$ 100,000	$ 100,000
Notes payable interest rate (as a percent)				6.18%	6.18%
Kennett \| 5.93% Surplus Note, due 2038
Related Party Transactions
Notes due to related parties				$ 50,000	$ 50,000
Notes payable interest rate (as a percent)				5.93%	5.93%
ALIC Re \| Kennett \| 6.74% Surplus Note, due 2029
Related Party Transactions
Notes due to related parties	$ 25,000
Notes payable interest rate (as a percent)	6.74%
Notes payable interest rate reset period	10 years
Basis spread over reference rate for reset of notes payable interest rate (as a percent)	3.25%
ALIC Re \| Kennett \| 5.06% Surplus Note, due 2035
Related Party Transactions
Notes due to related parties													$ 100,000
Notes payable interest rate (as a percent)								3.24%					5.06%
ALIC Re \| Kennett \| 6.18% Surplus Note, due 2036
Related Party Transactions
Notes due to related parties			$ 100,000
Notes payable interest rate (as a percent)			6.18%
Notes payable interest rate reset period			10 years
Basis spread over reference rate for reset of notes payable interest rate (as a percent)			1.14%
ALIC Re \| Kennett \| 5.93% Surplus Note, due 2038
Related Party Transactions
Notes due to related parties		$ 50,000
Notes payable interest rate (as a percent)		5.93%
Notes payable interest rate reset period		10 years
Basis spread over reference rate for reset of notes payable interest rate (as a percent)		2.09%
AIC \| 6.35% Note, due 2018
Related Party Transactions
Notes payable interest rate (as a percent)									6.35%
AIC \| 5.75% Note Two, due 2018
Related Party Transactions
Notes payable interest rate (as a percent)										5.75%
AIC \| 5.75% Note One, due 2018
Related Party Transactions
Notes payable interest rate (as a percent)											5.75%
Interest expense					$ 84	1,000
AIC \| 7.00% Surplus Note, due 2028
Related Party Transactions
Notes due to related parties												$ 400,000
Notes payable interest rate (as a percent)												7.00%
Interest expense						7,000
Repayment of principal amount						$ 200,000	$ 200,000
RBI \| Mortgage loans
Related Party Transactions
Fair value										$ 4,000
RBI \| Real estate
Related Party Transactions
Fair value											$ 10,000
RBI \| Fixed income securities
Related Party Transactions
Fair value									$ 7,000