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Stockholders' Equity (Common and Preferred Stock) (Details) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2018 Vote $ / shares shares | Dec. 31, 2017 $ / shares shares | Dec. 31, 2011 $ / shares shares
Private Placement [Member] |  |  |
Common Stock [Abstract] |  |  |
Common stock shares issued (in shares) |  |  | 20,000,000
Sale of Stock, Price Per Share | $ / shares |  |  | $ 10
Preferred Stock [Member] |  |  |
Preferred Stock [Abstract] |  |  |
Preferred shares authorized (in shares) | 8,990,000 |  |
Preferred shares issued (in shares) | 0 |  |
Common Class A [Member] |  |  |
Common Stock [Abstract] |  |  |
Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
Par value (in dollars per share) | $ / shares | $ 0.01 | $ 0.01 |
Common stock shares issued (in shares) | 17,667,857 | 17,667,857 |
Number of votes holder is entitled to | Vote | 1 |  |
Maximum individual common stock ownership (in hundredths) | 9.80% |  |
Common Class B [Member] |  |  |
Common Stock [Abstract] |  |  |
Common stock, shares authorized (in shares) | 1,000 |  |
Par value (in dollars per share) | $ / shares | $ 0.01 |  |
Common stock shares issued (in shares) | 0 |  |
Number of votes holder is entitled to | Vote | 1 |  |
Maximum individual common stock ownership (in hundredths) | 9.80% |  |

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- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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