GOODWILL AND OTHER INTANGIBLE ASSETS

The following table presents the changes in the carrying amount of goodwill and other intangible assets during the nine months ended September 30, 2018 ( in thousands):



	Goodwill		Other Intangible Assets			Total
Balance as of December 31, 2017	$	187,591	$	78,525		$	266,116
Acquired during the period	6,461		6,185			12,646
Translation adjustment	—		(352		)	(352		)
Amortization	—		(12,575		)	(12,575		)
Balance as of September 30, 2018	$	194,052	$	71,783		$	265,835

The following table presents the goodwill balance by reportable segment as of September 30, 2018 and December 31, 2017 (in thousands):



	September 30, 2018		December 31, 2017
Service Centers	$	160,934	$	154,473
Innovative Pumping Solutions	15,980		15,980
Supply Chain Services	17,138		17,138
Total	$	194,052	$	187,591

The following table presents a summary of amortizable other intangible assets ( in thousands):



	September 30, 2018							December 31, 2017
	Gross Carrying Amount		Accumulated Amortization			Carrying Amount, net		Gross Carrying Amount		Accumulated Amortization			Carrying Amount, net
Customer relationships	$	168,255	$	(96,639	)	71,616		162,200		(83,806		)	78,394
Non-compete agreements	784		(617		)	167		949		(818		)	131
Total	$	169,039	$	(97,256	)	$	71,783	$	163,149	$	(84,624	)	$	78,525

Gross carrying amounts as well as accumulated amortization are partially affected by the fluctuation of foreign currency rates. Other intangible assets are amortized according to estimated economic benefits over their estimated useful lives.