Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Thousands										3 Months Ended			5 Months Ended	6 Months Ended
	May 23, 2018	Feb. 14, 2018	Oct. 02, 2017	Aug. 04, 2017	Jul. 03, 2017	May 01, 2017	Jan. 31, 2017	Jul. 06, 2016	Feb. 04, 2016	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Assets Acquired
Goodwill										$ 248,998			$ 248,998	$ 248,998		$ 238,147
Adjustments
Gain on bargain purchase										0	$ 669			0	$ (11,574)
DirectACCESS Medical, LLC
Assets Acquired
Inventories	$ 971
Goodwill	938
Total assets acquired	7,269
Adjustments
Total purchase price	7,300
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		$ 6,039								5,804			5,804	5,804
Property and equipment		581								748			748	748
Goodwill		5,387								10,613			10,613	10,613
Total assets acquired		100,107								100,265			100,265	100,265
Adjustments
Inventories													(235)
Property and equipment													167
Goodwill													5,226
Total net assets acquired													158
Total purchase price		100,300
Becton, Dickinson and Company | Developed technology
Assets Acquired
Intangibles		79,900								74,000			74,000	74,000
Adjustments
Intangibles													(5,900)
Becton, Dickinson and Company | Customer lists
Assets Acquired
Intangibles		3,500								4,200			4,200	4,200
Adjustments
Intangibles													700
Becton, Dickinson and Company | Trademarks
Assets Acquired
Intangibles		$ 4,700								$ 4,900			4,900	$ 4,900
Adjustments
Intangibles													$ 200
ITL Healthcare Pty Ltd
Assets Acquired
Trade receivables			$ 1,287
Other receivables			56
Inventories			1,808
Prepaid expenses and other assets			65
Property and equipment			1,053
Goodwill			3,945
Total assets acquired			14,154
Liabilities Assumed
Trade payables			(216)
Accrued expenses			(747)
Deferred income tax liabilities			(1,901)
Total liabilities assumed			(2,864)
Total net assets acquired			11,290
Adjustments
Total purchase price			11,300
ITL Healthcare Pty Ltd | Customer lists
Assets Acquired
Intangibles			$ 5,940
Laurane Medical S.A.S.
Assets Acquired
Inventories				$ 594
Goodwill				6,366
Total assets acquired				22,000
Adjustments
Total purchase price				16,500
Laurane Medical S.A.S. | Developed technology
Assets Acquired
Intangibles				14,920
Laurane Medical S.A.S. | Customer lists
Assets Acquired
Intangibles				$ 120
Osseon LLC
Assets Acquired
Inventories					$ 979
Property and equipment					58
Goodwill					203
Total assets acquired					6,840
Adjustments
Total purchase price					6,800
Osseon LLC | Developed technology
Assets Acquired
Intangibles					5,400
Osseon LLC | Customer lists
Assets Acquired
Intangibles					$ 200
Vascular Access Technologies, Inc.
Assets Acquired
Goodwill						$ 4,281
Liabilities Assumed
Deferred income tax liabilities						(3,101)
Total net assets acquired						9,900
Adjustments
Total purchase price						5,000
Vascular Access Technologies, Inc. | Developed technology
Assets Acquired
Intangibles						7,800
Vascular Access Technologies, Inc. | In-process technology
Assets Acquired
Intangibles						$ 920
Argon Medical Devices, Inc.
Assets Acquired
Cash and cash equivalents											1,436				1,436
Trade receivables											8,351				8,351
Inventories											11,222				11,222
Prepaid expenses and other assets											1,275				1,275
Income tax refund receivables											165				165
Property and equipment											2,319				2,319
Deferred income tax assets											202				202
Total assets acquired											29,570				29,570
Liabilities Assumed
Trade payables											(2,414)				(2,414)
Accrued expenses											(5,083)				(5,083)
Deferred income tax liabilities											(934)				(934)
Total liabilities assumed											(8,431)				(8,431)
Total net assets acquired											21,139				21,139
Adjustments
Total net assets acquired							$ (797)
Gain on bargain purchase															(11,039)
Total purchase price							10,900								10,100
Negative adjustment (Argon Medical Devices, Inc.)												$ 1,200
Argon Medical Devices, Inc. | Developed technology
Assets Acquired
Intangibles											2,200				2,200
Argon Medical Devices, Inc. | Customer lists
Assets Acquired
Intangibles											1,500				1,500
Argon Medical Devices, Inc. | Trademarks
Assets Acquired
Intangibles											$ 900				$ 900
Catheter Connections, Inc.
Assets Acquired
Trade receivables							958
Inventories							2,157
Prepaid expenses and other assets							85
Property and equipment							1,472
Goodwill							8,989
Total assets acquired							38,361
Liabilities Assumed
Trade payables							(338)
Accrued expenses							(23)
Total liabilities assumed							(361)
Total net assets acquired							38,000
Adjustments
Total purchase price							38,000
Catheter Connections, Inc. | Developed technology
Assets Acquired
Intangibles							21,100
Catheter Connections, Inc. | Customer lists
Assets Acquired
Intangibles							700
Catheter Connections, Inc. | Trademarks
Assets Acquired
Intangibles							$ 2,900
DFINE, Inc.
Assets Acquired
Trade receivables								$ 4,054
Other receivables								6
Inventories								8,585
Prepaid expenses and other assets								630
Property and equipment								1,630
Other long-term assets								145
Goodwill								24,818
Total assets acquired								114,268
Liabilities Assumed
Trade payables								(1,790)
Accrued expenses								(5,298)
Deferred income tax liabilities - current								(701)
Deferred income tax liabilities - noncurrent								(10,844)
Total liabilities assumed								(18,633)
Total net assets acquired								95,635
Adjustments
Total purchase price								97,500
Cash received								1,327
DFINE, Inc. | Developed technology
Assets Acquired
Intangibles								67,600
DFINE, Inc. | Customer lists
Assets Acquired
Intangibles								2,400
DFINE, Inc. | Trademarks
Assets Acquired
Intangibles								$ 4,400
HeRO®Graft
Assets Acquired
Inventories									$ 2,455
Property and equipment									290
Goodwill									2,555
Total assets acquired									18,500
Adjustments
Total purchase price									18,500
HeRO®Graft | Developed technology
Assets Acquired
Intangibles									12,100
HeRO®Graft | Customer lists
Assets Acquired
Intangibles									400
HeRO®Graft | Trademarks
Assets Acquired
Intangibles									$ 700