Stockholders' Equity - Schedule of Repurchase Prices Under Share Repurchase Plan (Details)	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Less than 1 year	0.00%
1 year	92.50%
2 years	95.00%
3 years	97.50%
4 years	100.00%

Stock Repurchase Plan, Repurchase Price As Percentage of Estimate Fair Value, Anniversary Year 1

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Stock Repurchase Plan, Repurchase Price As Percentage of Estimate Fair Value, Anniversary Year 2

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Stock Repurchase Plan, Repurchase Price as Percentage of Estimated Fair Value, Anniversary Year 3

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Stock Repurchase Plan, Repurchase Price As Percentage of Estimate Fair Value, Anniversary Year 4

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Stock Repurchase Plan, Repurchase Price As Percentage of Estimate Fair Value, Within Twelve Months

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