Alternative investments as a percentage of overall invested assets.

No definition available.

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- Definition

Amortized cost of portfolio rated below investment grade.

+ References

No definition available.

+ Details

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

- Definition

This item represents the change in gross unrealized holding gain or loss on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Percentage of the fair value of portfolio that was rated investment grade as of balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

This item represents the percentage of the fair value of securities obtained as collateral under reverse repurchase agreements

+ References

No definition available.

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- Definition

Fair value of portfolio rated below investment grade.

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No definition available.

+ Details

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- Definition

Financing receivable, Number of loans past due

+ References

No definition available.

+ Details

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- Definition

Impaired financing receivable, number of impaired loans

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

This item represents total investment commitments as of the balance sheet date for fixed maturity available-for-sale securities, limited partnerships, real estate and mortgage loans on real estate.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

This item represents investment commitments as of the balance sheet date for limited partnerships.

+ References

No definition available.

+ Details

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

This item represents investment commitments as of the balance sheet date for private placements.

+ References

No definition available.

+ Details

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

This item represents investment commitments as of the balance sheet date for mortgage loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Investments [Line Items]

+ References

No definition available.

+ Details

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

- Definition

Number of partnerships represented in alternative investment portfolio.

+ References

No definition available.

+ Details

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Namespace Prefix:	lnc_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	instant

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

+ Details

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

- Definition

Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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Balance Type:	credit
Period Type:	instant

- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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-Paragraph 10A
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-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

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Period Type:	duration

- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

No definition available.

+ Details

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Investments (Narrative) (Details) $ in Millions	12 Months Ended
Investments (Narrative) (Details) $ in Millions	Dec. 31, 2020 USD ($) loan security item	Dec. 31, 2019 USD ($) security loan item	Dec. 31, 2018 USD ($)
Investments [Line Items]
Increase (decrease) in gross AFS securities unrealized losses	$ (45)
Unrealized gain (loss), trading securities	$ 118	$ 228	$ (58)
Number of partnerships in alternative investment portfolio \| item	271	258
Alternative investments as a percentage of overall invested assets	1.00%	1.00%
Net portion of OTTI recognized in OCI, pre-tax		$ 15	$ 0
Fair value of collateral received that we are permitted to sell or re-pledge	$ 25
Investment commitments	2,900
Investment commitments for limited partnerships	1,400
Investment commitments for mortgage loans on real estate	989
Investment commitments for private placements	$ 508
Minimum [Member]
Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	80.00%
Maximum [Member]
Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	95.00%
Federal Home Loan Mortgage Corporation [Member] \| Investments [Member]
Investments [Line Items]
Fair value	$ 1,200	$ 1,300
Concentration risk, percentage	1.00%	1.00%
Federal National Mortgage Association [Member] \| Investments [Member]
Investments [Line Items]
Fair value	$ 1,000	$ 1,000
Concentration risk, percentage	1.00%	1.00%
Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Investments [Line Items]
Fair value	$ 20,300	$ 16,300
Concentration risk, percentage	13.00%	12.00%
Financial Service [Member] \| Investments [Member]
Investments [Line Items]
Fair value	$ 19,600	$ 16,400
Concentration risk, percentage	13.00%	12.00%
Corporate Bonds [Member]
Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%	96.00%
Amortized cost of portfolio rated below investment grade	$ 4,100	$ 3,200
Fair value of portfolio rated below investment grade	$ 4,200	$ 3,300
Commercial [Member]
Investments [Line Items]
Number of impaired loans \| security	4	1
Impaired financing receivable, principal balance	$ 1
Commercial [Member] \| Maximum [Member]
Investments [Line Items]
Impaired financing receivable, principal balance		$ 1
Commercial [Member] \| Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| California [Member]
Investments [Line Items]
Concentration risk, percentage	24.00%	24.00%
Commercial [Member] \| Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Texas [Member]
Investments [Line Items]
Concentration risk, percentage	10.00%	11.00%
Residential [Member]
Investments [Line Items]
Number of loans past due \| loan	147	38
Number of impaired loans \| security	76	4
Impaired financing receivable, principal balance	$ 34	$ 1
Residential [Member] \| Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| California [Member]
Investments [Line Items]
Concentration risk, percentage	32.00%	34.00%
Residential [Member] \| Mortgage Loans On Real Estate [Member] \| Geographic Concentration Risk [Member] \| Florida [Member]
Investments [Line Items]
Concentration risk, percentage	18.00%	20.00%