Summary of Significant Accounting Policies - Additional Information (Details) |
12 Months Ended | |||
---|---|---|---|---|
Nov. 06, 2017 |
Jul. 21, 2016 |
Jul. 19, 2016 |
Dec. 31, 2017
Segment
|
|
Summary Of Significant Accounting Policies [Line Items] | ||||
Maximum period of investments with original maturities from date of acquisition to be cash equivalents | 3 months | |||
Reverse stock split ratio | 0.0029 | 0.0625 | ||
Number of business segments | 1 | |||
Minimum [Member] | ||||
Summary Of Significant Accounting Policies [Line Items] | ||||
Estimated useful lives | 3 years | |||
Reverse stock split ratio | 0.1 | |||
Maximum [Member] | ||||
Summary Of Significant Accounting Policies [Line Items] | ||||
Estimated useful lives | 7 years | |||
Reverse stock split ratio | 0.05 |