Goodwill and Intangible Assets

The following table summarizes changes in the carrying amount of goodwill in the Motorcycles segment for the following years ended December 31 (in thousands):



	2018			2017		2016
Balance, beginning of period	$	55,947		$	53,391	$	54,182
Currency translation	(899		)	2,556		(791		)
Balance, end of period	$	55,048		$	55,947	$	53,391

The following table summarizes the Motorcycles segment intangible assets other than goodwill at December 31 (in thousands):



	2018
	Gross Carrying Amount	Accumulated Amortization		Net	Estimated useful life (years)
Customer relationships	7,234	(1,236	)	5,998	20



	2017
	Gross Carrying Amount	Accumulated Amortization		Net	Estimated useful life (years)
Customer relationships	7,860	(950	)	6,910	20

Intangible assets other than goodwill are included in other long-term assets on the Company's consolidated balance sheets. The gross carrying amounts at December 31 differ from the acquisition date amounts due to changes in foreign currency exchange rates.

Total amortization expense of other intangible assets was $0.4 million, $4.2 million and $7.0 million for 2018, 2017 and 2016, respectively. The Company estimates future amortization to be as follows (in thousands):



	Estimated Amortization
2019	$	372
2020	372
2021	372
2022	372
2023	372
Thereafter	4,138
Total	$	5,998

The Financial Services segment had no goodwill or intangible assets at December 31, 2018 and 2017.