Goodwill and Intangible Assets - (Tables)

9 Months Ended

Sep. 30, 2019

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, 2018	$	927,630
Foreign exchange	(20,905		)
Balance at September 30, 2019	$	906,725

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): 

	September 30, 2019								December 31, 2018
	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	13.5	$	3,136,957	$	(790,075	)	$	2,346,882	$	3,110,641	$	(632,413	)	$	2,478,228
Priority review voucher		111,101		—			111,101		111,101		—			111,101
Manufacturing contracts	—	11,656		(11,656		)	—		12,256		(12,256		)	—
Trademarks	—	2,881		(2,881		)	—		2,896		(2,896		)	—
Total finite-lived intangible assets		3,262,595		(804,612		)	2,457,983		3,236,894		(647,565		)	2,589,329
Acquired IPR&D assets		135,047		—			135,047		142,005		—			142,005
Total intangible assets		$	3,397,642	$	(804,612	)	$	2,593,030	$	3,378,899	$	(647,565	)	$	2,731,334

Estimated Future Amortization Costs

Based on finite-lived intangible assets recorded as of September 30, 2019, 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
2019 (remainder)	$	173,131
2020	246,957
2021	201,390
2022	157,785
2023	157,785
Thereafter	1,520,935
Total	$	2,457,983