Shareholders' Equity

12 Months Ended

Dec. 31, 2020

Stockholders' Equity Note [Abstract]

Shareholders' Equity

Shareholders’ Equity

Shares of common stock

The following table summarizes total shares of common stock outstanding:

	December 31
Millions of shares	2020	2019
Issued	1,066	1,068
In treasury	(181)	(190)
Total shares of common stock outstanding	885	878

Our Board of Directors has authorized a program to repurchase a specified dollar amount of our common stock from time to time. The program does not require a specific number of shares to be purchased and the program may be effected through solicited or unsolicited transactions in the market or in privately negotiated transactions. The program may be terminated or suspended at any time. During the year ended December 31, 2020 we repurchased approximately 7.4 million shares of our common stock for a total cost of $100 million. There were 4.5 million repurchases made under the program during the year ended December 31, 2019. Approximately $5.1 billion remained authorized for repurchases as of December 31, 2020. From the inception of this program in February 2006 through December 31, 2020, we repurchased approximately 224 million shares of our common stock for a total cost of approximately $9.0 billion.

Paid-in Capital in Excess of Par Value

During 2020, we issued common stock from treasury shares under our employee stock purchase plan awards and for restricted stock grants. As a result, additional paid in capital was reduced below zero, which resulted in a reduction of retained earnings by $75 million. Additional issuances from treasury shares could similarly impact additional paid in capital and retained earnings.

Preferred stock

Our preferred stock consists of five million total authorized shares at December 31, 2020, of which none are issued.

Accumulated other comprehensive loss

Accumulated other comprehensive loss consisted of the following:

	December 31
Millions of dollars	2020		2019
Defined benefit and other postretirement liability adjustments (a)	$	(226)	$	(214)
Cumulative translation adjustment	(83)		(82)
Other	(53)		(66)
Total accumulated other comprehensive loss	$	(362)	$	(362)

    (a) Included net actuarial losses for our international pension plans of $212 million at December 31, 2020 and $189 million at December 31, 2019.