Description of Business and Summary of Significant Accounting Policies (Recent Accounting Pronouncements) (Details) - USD ($) $ in Millions |
|
9 Months Ended |
12 Months Ended |
Jan. 01, 2017 |
Sep. 30, 2017 |
Dec. 31, 2016 |
| Accounting Standards Update 2016-09 | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Recognition of excess tax benefits |
|
$ 9.6
|
|
| Increase in net valuation allowance |
|
$ 9.6
|
|
| Accounting Standards Update 2014-09 | Maximum | Revenue Streams | Overall Revenue |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Concentration risk, percentage |
|
|
5.00%
|
| Accumulated Deficit | Accounting Standards Update 2016-09 | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| New accounting pronouncement, cumulative effect of change, accumulated deficit increase (decrease) |
$ 0.3
|
|
|
| State |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Unrecorded tax benefits for stock-based compensation |
|
|
$ 17.6
|
| Domestic | Accounting Standards Update 2016-09 | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Deferred tax assets, operating loss carryforwards |
7.7
|
|
|
| Domestic | Accounting Standards Update 2016-09 | Valuation allowance, operating loss carryforwards | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Increase in net valuation allowance |
7.7
|
|
|
| Domestic | Accumulated Deficit | Accounting Standards Update 2016-09 | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| New accounting pronouncement, cumulative effect of change, accumulated deficit increase (decrease) |
(7.7)
|
|
|
| Domestic | Accumulated Deficit | Accounting Standards Update 2016-09 | Valuation allowance, operating loss carryforwards | Adjustment |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| New accounting pronouncement, cumulative effect of change, accumulated deficit increase (decrease) |
$ 7.7
|
|
|
| Federal |
|
|
|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
|
|
|
| Unrecorded tax benefits for stock-based compensation |
|
|
$ 20.6
|