Acquisitions - Purchase Price Allocation (Argon Medical Devices, Inc.) (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 31, 2017	Mar. 31, 2017	Mar. 31, 2016
Business Acquisition [Line Items]
Gain on bargain purchase		$ (12,243)	$ 0
Argon Medical Devices, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		1,436
Trade receivables		8,351
Inventories		12,217
Prepaid expenses		1,275
Property and equipment		2,667
Deferred tax assets		184
Total assets acquired		31,530
Trade payables		(2,306)
Accrued expenses		(5,083)
Income taxes payable		(2)
Deferred income tax liabilities - noncurrent		(999)
Total liabilities assumed		8,390
Total net assets acquired		23,140
Gain on bargain purchase		(12,243)
Total purchase price	$ 10,897
Developed technology | Argon Medical Devices, Inc.
Business Acquisition [Line Items]
Intangibles		2,600
Customer Lists | Argon Medical Devices, Inc.
Business Acquisition [Line Items]
Intangibles		1,300
Trademarks | Argon Medical Devices, Inc.
Business Acquisition [Line Items]
Intangibles		$ 1,500