Amount of the cumulative effect on retained earnings net of related income tax effect.

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Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Revenue (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 360,460	$ 331,514	$ 732,493	$ 579,253
Cumulative Effect on Retained Earnings, Net of Tax			6,300
Infusion Systems [Member]
Disaggregation of Revenue [Line Items]
Revenues	88,376	$ 73,122	181,815	$ 119,792
Infusion Systems [Member] \| Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues	4,600		5,900
Equipment revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation	6,500		6,500
Software revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation	$ 1,500		$ 1,500