SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2017

The following table sets forth the aging of our net accounts receivable (net of allowance for contractual adjustments and prior to allowance for doubtful accounts), aged based on date of service and categorized based on the three primary overall types of accounts receivable characteristics (in thousands):



	December 31, 2017									December 31, 2016
	0 - 180 days		Over 180 days		Total			% of Total		0 - 180 days		Over 180 days		Total			% of Total
Government	$	20,602	$	10,082	$	30,684				$	19,891	$	8,278	$	28,169
Commercial	63,767		18,779		82,546					95,018		19,849		114,867
Patient	2,577		7,627		10,204					3,955		6,825		10,780
Gross accounts receivable	$	86,946	$	36,488	123,434					$	118,864	$	34,952	153,816
Allowance for doubtful accounts					(37,912		)	30.7	%					(44,730		)	29.1	%
Net accounts receivable					$	85,522								$	109,086

Estimated useful lives of assets

Property and equipment is stated at cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of assets as follows:



Asset	Useful Life
Computer hardware and software	3	years	-	5	years
Office equipment				5	years
Vehicles	4	years	-	5	years
Medical equipment	13	months	-	5	years
Furniture and fixtures				5	years