Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of changes in allowance for doubtful accounts

The changes in the allowance for doubtful accounts consisted of the following:



	Year Ended December 31,
In thousands	2017			2016			2015
Balance at beginning of year	$	1,028		$	974		$	878
Net charges to expense	192			711			685
Amounts recovered against the allowance	(523		)	(657		)	(589		)
Balance at end of year	$	697		$	1,028		$	974

Schedule of estimated useful lives of property, plant and equipment

Property, plant and equipment are stated on the basis of cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. The general ranges of estimated useful lives are:



Buildings and improvements	3	to	40 years
Software	2	to	10 years
Equipment and furniture	3	to	20 years

Schedule of capital lease assets

Capital lease assets are included in property, plant and equipment. Capital lease assets at December 31, 2017 and 2016 consisted of:



	December 31,
In thousands	2017			2016
Equipment and furniture	$	1,774		$	2,357
Less accumulated depreciation	(687		)	(903		)
Net book value	$	1,087		$	1,454

Schedule of information about the operations in different geographical areas

Information about the operations in different geographic areas:



	Year Ended December 31,
In thousands	2017		2016		2015
Revenue (1)
United States	$	330,944	$	324,625	$	377,717
Other countries	52,962		79,787		66,449
Total revenue	$	383,906	$	404,412	$	444,166



	December 31,
In thousands	2017		2016
Property, plant and equipment (2)
United States	$	18,789	$	19,810
Other countries	2,998		4,114
Total property, plant and equipment	$	21,787	$	23,924


(1)	Geographic revenues are based on the location of the service being performed.


(2)	Property, plant and equipment are based on physical location.