Stockholders' Equity - Additional Information (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Aug. 22, 2016 |
Aug. 22, 2016 |
Aug. 12, 2016 |
May 09, 2016 |
Sep. 30, 2016 |
Sep. 30, 2016 |
Sep. 30, 2015 |
Dec. 31, 2015 |
|
| Equity [Abstract] | ||||||||
| Stock Issued During Period, Shares, New Issues | 1,300,000 | 10,000,000 | ||||||
| Maximum shares for over-allotment option | 1,500,000 | |||||||
| Proceeds from public offering, net of issuance costs | $ 258,600,000 | $ 286,583,000 | $ 317,822,000 | |||||
| Class A common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | ||||
| Common stock to be issued under trading agreement | $ 200,000,000 | |||||||
| Shares Sold Under the Equity Distribution Agreement | 1,240,504 | 1,240,504 | ||||||
| Net Proceeds from Issuances Under Equity Distribution Agreement | $ 27,600,000 | $ 27,600,000 | ||||||
| Payments to Agents for stock issuances under Equity Distribution Agreement | $ 300,000 | $ 292,330.95 | ||||||