Accounts Receivable, Accounts Payable and Accrued Liabilities

12 Months Ended

Dec. 31, 2017

Accounts Receivable Accounts Payable And Accrued Liabilities [Abstract]

Accounts Receivable Accounts Payable And Accrued Liabilities

ACCOUNTS RECEIVABLE, ACCOUNTS PAYABLE AND ACCRUED LIABILITIES

Accounts receivable consist of the following:

	As of December 31
(in thousands)	2017		2016
Trade accounts receivable, less doubtful accounts of $22,975 and $26,723	$	600,215	$	591,854
Other receivables	20,104		23,247
	$	620,319	$	615,101

The changes in allowance for doubtful accounts was as follows:

(in thousands)	Balance at Beginning of Period		Additions – Charged to Costs and Expenses		Deductions			Balance at End of Period
2017	$	26,723	$	33,830	$	(37,578	)	$	22,975
2016	$	27,854	$	29,718	$	(30,849	)	$	26,723
2015	$	32,598	$	39,982	$	(44,726	)	$	27,854

Accounts payable and accrued liabilities consist of the following:

	As of December 31
(in thousands)	2017		2016
Accounts payable and accrued liabilities	$	385,927	$	352,356
Accrued compensation and related benefits	140,396		148,370
	$	526,323	$	500,726

Cash overdrafts of $6.0 million and $15.5 million are included in accounts payable and accrued liabilities at December 31, 2017 and 2016, respectively.