TriVascular Merger (Carrying Amount of Goodwill) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 28,685
Goodwill, ending balance	120,693
TriVascular Technologies, Inc.
Goodwill [Roll Forward]
Goodwill, beginning balance	28,685
Foreign currency translation adjustment	$ 23