Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Aug. 01, 2019	Jun. 14, 2019	Dec. 31, 2018	Dec. 14, 2018	Nov. 13, 2018	May 23, 2018	Feb. 14, 2018
Assets Acquired
Goodwill	$ 352,158			$ 335,433
Fibrovein Holdings Limited
Assets Acquired
Trade receivables		$ 200
Inventories		843
Prepaid expenses and other assets		49
Intangibles		10,148
Goodwill		4,390
Total assets acquired		15,630
Liabilities Assumed
Trade payables		(53)
Accrued expenses		(29)
Deferred income tax liabilities		(1,875)
Total liabilities assumed		(1,957)
Total net assets acquired		$ 13,673
Brightwater
Assets Acquired
Trade receivables			$ 55
Inventories			349
Property and equipment			409
Other long-term assets			30
Goodwill			17,909
Total assets acquired			51,045
Liabilities Assumed
Trade payables			(58)
Accrued expenses			(261)
Other long-term liabilities			(1,522)
Deferred income tax liabilities			(4,590)
Total liabilities assumed			(6,431)
Total net assets acquired			44,614
Brightwater | Adjusments
Assets Acquired
Trade receivables			(39)
Goodwill			959
Total assets acquired			1,200
Liabilities Assumed
Total net assets acquired			1,200
Brightwater | Preliminary Allocation
Assets Acquired
Trade receivables			94
Inventories			349
Property and equipment			409
Other long-term assets			30
Goodwill			16,950
Total assets acquired			49,845
Liabilities Assumed
Trade payables			(58)
Accrued expenses			(261)
Other long-term liabilities			(1,522)
Deferred income tax liabilities			(4,590)
Total liabilities assumed			(6,431)
Total net assets acquired			43,414
Brightwater | Developed technology
Assets Acquired
Intangibles			31,960
Brightwater | Developed technology | Adjusments
Assets Acquired
Intangibles			280
Brightwater | Developed technology | Preliminary Allocation
Assets Acquired
Intangibles			31,680
Brightwater | Customer Lists
Assets Acquired
Intangibles			83
Brightwater | Customer Lists | Preliminary Allocation
Assets Acquired
Intangibles			83
Brightwater | Trademarks
Assets Acquired
Intangibles			250
Brightwater | Trademarks | Preliminary Allocation
Assets Acquired
Intangibles			$ 250
Vascular Insights
Assets Acquired
Inventories					$ 1,353
Goodwill					21,832
Total assets acquired					58,185
Vascular Insights | Developed technology
Assets Acquired
Intangibles					32,750
Vascular Insights | Customer Lists
Assets Acquired
Intangibles					840
Vascular Insights | Trademarks
Assets Acquired
Intangibles					$ 1,410
Cianna Medical
Assets Acquired
Trade receivables						$ 6,151
Inventories						5,803
Prepaid expenses and other assets						315
Property and equipment						1,047
Other long-term assets						14
Goodwill						61,379
Total assets acquired						219,629
Liabilities Assumed
Trade payables						(1,497)
Accrued expenses						(2,384)
Other long-term liabilities						(1,527)
Deferred income tax liabilities						(25,940)
Total liabilities assumed						(31,348)
Total net assets acquired						188,281
Cianna Medical | Adjusments
Assets Acquired
Goodwill						(4,506)
Total assets acquired						(4,506)
Liabilities Assumed
Deferred income tax liabilities						4,423
Total liabilities assumed						4,423
Total net assets acquired						(83)
Cianna Medical | Preliminary Allocation
Assets Acquired
Trade receivables						6,151
Inventories						5,803
Prepaid expenses and other assets						315
Property and equipment						1,047
Other long-term assets						14
Goodwill						65,885
Total assets acquired						224,135
Liabilities Assumed
Trade payables						(1,497)
Accrued expenses						(2,384)
Other long-term liabilities						(1,527)
Deferred income tax liabilities						(30,363)
Total liabilities assumed						(35,771)
Total net assets acquired						188,364
Cianna Medical | Developed technology
Assets Acquired
Intangibles						134,510
Cianna Medical | Developed technology | Preliminary Allocation
Assets Acquired
Intangibles						134,510
Cianna Medical | Customer Lists
Assets Acquired
Intangibles						3,330
Cianna Medical | Customer Lists | Preliminary Allocation
Assets Acquired
Intangibles						3,330
Cianna Medical | Trademarks
Assets Acquired
Intangibles						7,080
Cianna Medical | Trademarks | Preliminary Allocation
Assets Acquired
Intangibles						$ 7,080
DirectACCESS Medical, LLC
Assets Acquired
Inventories							$ 971
Goodwill							938
Total assets acquired							7,269
DirectACCESS Medical, LLC | Developed technology
Assets Acquired
Intangibles							4,840
DirectACCESS Medical, LLC | Customer Lists
Assets Acquired
Intangibles							120
DirectACCESS Medical, LLC | Trademarks
Assets Acquired
Intangibles							$ 400
Becton, Dickinson and Company
Assets Acquired
Inventories								$ 5,804
Property and equipment								748
Goodwill								9,728
Total assets acquired								101,880
Becton, Dickinson and Company | Developed technology
Assets Acquired
Intangibles								74,000
Becton, Dickinson and Company | Customer Lists
Assets Acquired
Intangibles								4,200
Becton, Dickinson and Company | Trademarks
Assets Acquired
Intangibles								4,900
Becton, Dickinson and Company | In-process technology
Assets Acquired
Intangibles								$ 2,500