Supplemental Disclosures (Tables)

12 Months Ended

Dec. 31, 2020

Supplemental Cash Flow Information [Abstract]

Additional information concerning acquisitions, interest and income taxes paid

The following schedule provides additional information concerning acquisitions, interest and income taxes paid:

(In millions of dollars)	2020		2019		2018
Assets acquired, excluding cash	$	929	$	8,655	$	1,100
Liabilities assumed	(78)		(2,804)		(83)
Non-controlling interests assumed	—		(280)		—
Contingent and deferred purchase consideration	(183)		(66)		(133)
Net cash outflow for acquisitions	$	668	$	5,505	$	884

(In millions of dollars)	2020		2019		2018
Interest paid	$	481	$	427	$	264
Income taxes paid, net of refunds	$	673	$	661	$	632

Analysis of allowance for doubtful accounts

An analysis of the allowance for credit losses for the year ended December 31, 2020 is provided below. Prior periods analysis is based on the Company's allowance for doubtful accounts model prior to adoption of the new accounting guidance discussed above:

For the Years Ended December 31,
(In millions of dollars)	2020		2019		2018
Balance at beginning of year	$	140	$	112	$	110
Provision charged to operations	47		32		34
Accounts written-off, net of recoveries	(30)		(16)		(24)
Effect of exchange rate changes and other	(15)		12		(8)
Balance at end of year	$	142	$	140	$	112