Stock-Based Incentive Compensation Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restricted Stock Units [Member]
Narrative [Abstract]
Percentage of total awards granted during the year for participating executive officers	42.00%	40.00%	41.00%
Stock awards granted (in shares)	448,527	767,733	481,900
Performance Shares [Member]
Narrative [Abstract]
Percentage of total awards granted during the year for participating executive officers	35.00%	36.00%	35.00%
Percentage of target award opportunities, minimum	0.00%	0.00%	0.00%
Percentage of target award opportunities, maximum	200.00%	200.00%	200.00%
Stock awards granted (in shares)	154,351	291,298	161,255
Stock options with performance conditions [Member]
Narrative [Abstract]
Option awards granted (in shares)	102,728
Total fair value of options vested	$ 2	$ 1	$ 1
Total intrinsic value of options exercised	$ 12	$ 3	$ 2
Stock options with service conditions [Member]
Narrative [Abstract]
Percentage of total awards granted during the year for participating executive officers	23.00%	24.00%	24.00%
Maximum Contractual Term (In Years)	10 years	10 years	10 years
Vesting period (in years)	3 years	3 years	3 years
Option awards granted (in shares)	407,637	776,895	502,664
Total fair value of options vested	$ 6	$ 6	$ 7
Total intrinsic value of options exercised	$ 23	22	25
Non-employee Stock Appreciation Rights [Member]
Narrative [Abstract]
Vesting period (in years)	4 years
Percentage of SARs vesting each year over four-year period	25.00%
Option awards granted (in shares)	26,494
SARs liability	$ 3	4
Payment for SARs exercised	$ 3	$ 2	$ 2

The expiration period of LNC stock options

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- Definition

The maximum percentage of target award opportunities that may be paid out in shares, cash or a combination of shares and cash, depending on performance results.

+ References

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The minimum percentage of target award opportunities that may be paid out in shares, cash or a combination of shares and cash, depending on performance results.

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- Definition

Percentage of the total awards granted during the year, by award type, for participating executive officers.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

No definition available.

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The total fair value of share-based awards for which the grantee gained the right during the reporting period, by satisfying service or performance requirements, to receive or retain shares, options, or cash in accordance with the terms of the arrangement.

+ References

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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No definition available.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (k)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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