Revenue (Comprehensive Income) (Details) - USD ($)
$ in Thousands |
3 Months Ended |
Mar. 31, 2018 |
Mar. 31, 2017 |
| Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |
|
|
| Net loss |
$ (46,472)
|
$ (54,647)
|
| Foreign currency translation |
586
|
(824)
|
| Net unrealized loss on available-for-sale securities |
(849)
|
0
|
| Comprehensive Income (Loss), Net of Tax, Attributable to Parent |
(46,735)
|
$ (55,471)
|
| Impacts from Adoption | Accounting Standards Update 2014-09 [Member] |
|
|
| Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |
|
|
| Net loss |
(32,554)
|
|
| Foreign currency translation |
(289)
|
|
| Net unrealized loss on available-for-sale securities |
0
|
|
| Comprehensive Income (Loss), Net of Tax, Attributable to Parent |
(32,843)
|
|
| Without Adoption (ASC 605) |
|
|
| Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |
|
|
| Net loss |
(79,026)
|
|
| Foreign currency translation |
297
|
|
| Net unrealized loss on available-for-sale securities |
(849)
|
|
| Comprehensive Income (Loss), Net of Tax, Attributable to Parent |
$ (79,578)
|
|