Goodwill and Other Intangible Assets, Net

The following is a summary of the carrying value of goodwill by operating segment.



(in thousands)	Retirement Centers		Assisted Living			Brookdale Ancillary Services		Total
Balance at January 1, 2018	$	27,321	$	351,652		$	126,810	$	505,783
Impairment	—		(351,652		)	—		(351,652		)
Balance at June 30, 2018	$	27,321	$	—		$	126,810	$	154,131

Goodwill is tested for impairment annually with a test date of October 1 or sooner if indicators of impairment are present. The Company determined no impairment was necessary for the three months ended June 30, 2018. Factors the Company considers important in its analysis, which could trigger an impairment of such assets, include significant underperformance relative to historical or projected future operating results, significant negative industry or economic trends, a significant decline in the Company's stock price for a sustained period and a decline in its market capitalization below net book value. A change in anticipated operating results or the other metrics indicated above could necessitate further analysis of potential impairment at an interval prior to the Company's annual measurement date. Refer to Note 5 for information on impairment expense for goodwill.

The following is a summary of other intangible assets.



	June 30, 2018
(in thousands)	Gross Carrying Amount		Accumulated Amortization			Net
Community purchase options	$	4,738	$	—		$	4,738
Health care licenses	49,250		—			49,250
Trade names	27,800		(25,006		)	2,794
Management contracts	10,680		(7,645		)	3,035
Total	$	92,468	$	(32,651	)	$	59,817



	December 31, 2017
(in thousands)	Gross Carrying Amount		Accumulated Amortization			Net
Community purchase options	$	9,533	$	—		$	9,533
Health care licenses	50,927		—			50,927
Trade names	27,800		(23,714		)	4,086
Management contracts	11,360		(7,929		)	3,431
Total	$	99,620	$	(31,643	)	$	67,977

Amortization expense related to definite-lived intangible assets for the three months ended June 30, 2018 and 2017 was $0.8 million and $3.0 million, respectively, and for the six months ended June 30, 2018 and 2017 was $1.7 million and $3.9 million, respectively.

Health care licenses were determined to be indefinite-lived intangible assets and are not subject to amortization. The community purchase options are not currently amortized, but will be added to the cost basis of the related communities if the option is exercised, and will then be depreciated over the estimated useful life of the community.