MARKETABLE SECURITIES (Tables)

12 Months Ended

Dec. 31, 2021

Marketable Securities [Abstract]

Summary of marketable securities

A summary of marketable securities, all of which are classified as current, was as follows:

	December 31,
	2021						2020
In millions	Cost		Gross unrealized gains/(losses) (1)		Estimated fair value		Cost		Gross unrealized gains/(losses) (1)		Estimated fair value
Equity securities
Certificates of deposit	$	299	$	—	$	299	$	164	$	—	$	164
Debt mutual funds	254		2		256		267		5		272
Equity mutual funds	29		10		39		19		5		24
Debt securities	1		—		1		1		—		1
Total marketable securities	$	583	$	12	$	595	$	451	$	10	$	461
(1) Unrealized gains and losses for debt securities are recorded in other comprehensive income while unrealized gains and losses for equity securities are recorded in "Other income, net" in our Consolidated Statements of Net Income.

Schedule of proceeds from sales and maturities of marketable securities

The proceeds from sales and maturities of marketable securities were as follows:

	Years ended December 31,
In millions	2021		2020		2019
Proceeds from sales of marketable securities	$	494	$	343	$	258
Proceeds from maturities of marketable securities	179		126		131
Investments in marketable securities - liquidations	$	673	$	469	$	389