Supplemental Disclosures (Tables)

12 Months Ended

Dec. 31, 2017

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)	2017			2016			2015
Assets acquired, excluding cash	$	898		$	960		$	1,327
Liabilities assumed	(134		)	(111		)	(199		)
Contingent/deferred purchase consideration	(109		)	(36		)	(176		)
Net cash outflow for acquisitions	$	655		$	813		$	952

(In millions of dollars)	2017		2016		2015
Interest paid	$	199	$	178	$	146
Income taxes paid, net of refunds	$	583	$	642	$	433

Analysis of allowance for doubtful accounts

An analysis of the allowance for doubtful accounts is as follows:

For the Years Ended December 31,
(In millions of dollars)	2017			2016			2015
Balance at beginning of year	$	96		$	87		$	95
Provision charged to operations	31			31			14
Accounts written-off, net of recoveries	(17		)	(20		)	(18		)
Effect of exchange rate changes and other	—			(2		)	(4		)
Balance at end of year	$	110		$	96		$	87