Summary of Significant Accounting Policies - Stock-Based Compensation Expense (Details) - USD ($) |
Dec. 31, 2018 |
Jan. 01, 2018 |
Jan. 01, 2017 |
|---|---|---|---|
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Deferred income tax assets, net | $ 0 | $ 0 | |
| ASU 2016-09 | |||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |||
| Deferred income tax assets, net | $ 4,000,000 |
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Details
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