Stockholders' Equity and Earnings Per Common Share (Tables)

12 Months Ended

Dec. 31, 2020

Stockholders' Equity and Earnings Per Common Share [Abstract]

Schedule of Basic and Diluted Earnings Per Share

Net income per common share is determined as follows:

	Year Ended December 31
	2020		2019		2018
	(in millions of dollars, except share data)
Numerator
Net Income	$	793.0	$	1,100.3	$	523.4
Denominator (000s)
Weighted Average Common Shares - Basic	203,642.0		209,728.9		219,635.6
Dilution for Assumed Exercises of Stock Options and Nonvested Stock Awards	113.3		125.5		423.0
Weighted Average Common Shares - Assuming Dilution	203,755.3		209,854.4		220,058.6
Net Income Per Common Share
Basic	$	3.89	$	5.25	$	2.38
Assuming Dilution	$	3.89	$	5.24	$	2.38

Treasury Stock Transactions

During the second quarter of 2019, our board of directors authorized the repurchase of up to $750.0 million of Unum Group's outstanding common stock through November 23, 2020, at which point the authorization expired. This authorization replaced the previous authorization of $750.0 million that was scheduled to expire on November 24, 2019. As of December 31, 2020, we did not authorize a new share repurchase program and there were no remaining amounts to be repurchased under either plan at December 31, 2020.

Common stock repurchases, which are accounted for using the cost method and classified as treasury stock until otherwise retired, were as follows:

	Year Ended December 31
	2020		2019		2018
	(in millions)
Shares Repurchased	—		12.3		8.7
Cost of Shares Repurchased (1)	$	—	$	400.4	$	350.7

(1) Includes commissions of $0.4 million and $0.7 million for the years ended December 31, 2019 and 2018, respectively.