Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Summary of Significant Accounting Policies [Abstract]

Contract with Customer, Asset and Liability [Table Text Block]

The following table provides 2020 and 2019 information about receivables and deferred revenue, which represent contract liabilities from contracts with customers:

	2020				2019
Contract balance information	Trade Receivables		Contract liabilities		Trade Receivables		Contract liabilities
Balance at January 1	$	619.3	$	320.5	$	737.2	$	378.2
Balance at December 31	$	646.9	$	346.8	$	619.3	$	320.5

Accounts Receivable, Allowance for Credit Loss

The following table summarizes the Company’s allowances for doubtful accounts:

	2020		2019		2018
Balance at January 1	$	42.2	$	58.2	$	71.7
Charged to costs and expenses	10.1		5.2		22.8
Charged to other accounts (1)	(1.2)		(0.9)		(4.1)
Deductions (2)	(13.6)		(20.3)		(32.2)
Balance at December 31	$	37.5	$	42.2	$	58.2

(1)    Net effects of foreign currency translation.

(2)    Uncollectible accounts written-off, net of recoveries.