Shares and Stockholders' Equity - Reconciliation of the Denominator Calculations of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Net income (loss) available to common stockholders – basic	$ 3,184	$ (834)	$ 1,358
Deferred units of LNC stock in our deferred compensation plans	3	(1)	(13)
Net income (loss) available to common stockholders	$ 3,187	$ (835)	$ 1,345
Weighted-average shares, as used in basic calculation (in shares)	170,597,104	169,562,903	171,034,695
Incremental common shares from assumed exercise or issuance of stock-based incentive compensation awards (in shares)	1,789,530	570,943	1,152,890
Average deferred compensation shares (in shares)	693,791	604,809	512,570
Weighted-average shares, as used in diluted calculation (in shares)	173,080,425	170,738,655	172,700,155
Net income (loss) per share:
Basic (in dollars per share)	$ 18.66	$ (4.92)	$ 7.93
Diluted (in dollars per share)	$ 18.41	$ (4.92)	$ 7.78