Workers' Compensation Claims (Tables)

6 Months Ended

Jun. 30, 2018

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Summarizes Aggregate Workers' Compensation Reserve Activity

The following table summarizes the aggregate workers’ compensation reserve activity (in thousands):

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2018			2017			2018			2017
Beginning balance
Workers' compensation claims liabilities	$	378,874		$	326,233		$	363,517		$	312,537
Add: claims expense accrual
Current period		39,967			37,878			79,019			73,153
Prior periods		—			2,350			(6	)		5,264
		39,967			40,228			79,013			78,417
Less: claim payments related to
Current period		5,148			4,148			6,281			5,280
Prior periods		22,856			25,998			45,391			49,462
		28,004			30,146			51,672			54,742
Add: Change in claims incurred in excess of retention      limits		(23	)		(6,236	)		(44	)		(6,133	)
Ending balance
Workers' compensation claims liabilities	$	390,814		$	330,079		$	390,814		$	330,079
Incurred but not reported (IBNR)	$	231,702		$	167,693		$	231,702		$	167,693
Ratio of IBNR to workers' compensation claims      liabilities		59	%		51	%		59	%		51	%