Segment Information (Long-Lived Assets by Geographic Region) (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total long-lived assets		$ 173,849	$ 155,018
United States
Segment Reporting Information [Line Items]
Total long-lived assets		135,894	121,894
Israel
Segment Reporting Information [Line Items]
Total long-lived assets		16,657	13,598
Australia
Segment Reporting Information [Line Items]
Total long-lived assets		9,293	8,970
Netherlands
Segment Reporting Information [Line Items]
Total long-lived assets		7,344	7,426
Other
Segment Reporting Information [Line Items]
Total long-lived assets	[1]	$ 4,661	$ 3,130

[1] United Kingdom, Germany, Japan, France and Italy