Goodwill and Intangible Assets - (Tables)

3 Months Ended

Mar. 31, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Gross Carrying Amount of Goodwill

The gross carrying amount of goodwill was as follows (in thousands):

Balance at December 31, 2019	$	920,018
Foreign exchange	(10,792		)
Balance at March 31, 2020	$	909,226

Gross Carrying Amounts and Net Book Values of Intangible Assets

The gross carrying amounts and net book values of our intangible assets were as follows (in thousands): 

	March 31, 2020								December 31, 2019
	Remaining Weighted- Average Useful Life (In years)	Gross Carrying Amount		Accumulated Amortization			Net Book Value		Gross Carrying Amount		Accumulated Amortization			Net Book Value
Acquired developed technologies	13.2	$	3,152,634	$	(913,976	)	$	2,238,658	$	3,166,485	$	(864,834	)	$	2,301,651
Manufacturing contracts	—	11,728		(11,728		)	—		12,025		(12,025		)	—
Trademarks	—	2,883		(2,883		)	—		2,890		(2,890		)	—
Priority review voucher	—	—		—			—		111,101		(111,101		)	—
Total finite-lived intangible assets		3,167,245		(928,587		)	2,238,658		3,292,501		(990,850		)	2,301,651
Acquired IPR&D assets		—		—			—		139,326		—			139,326
Total intangible assets		$	3,167,245	$	(928,587	)	$	2,238,658	$	3,431,827	$	(990,850	)	$	2,440,977

Estimated Future Amortization Costs

Based on finite-lived intangible assets recorded as of March 31, 2020, and assuming the underlying assets will not be impaired and that we will not change the expected lives of the assets, future amortization expenses were estimated as follows (in thousands): 

Year Ending December 31,	Estimated Amortization   Expense
2020 (remainder)	$	186,372
2021	203,041
2022	159,167
2023	159,167
2024	159,167
Thereafter	1,371,744
Total	$	2,238,658