Share-Based Payments - Summary of Status and Changes of Unvested Restricted Stock (Details)	12 Months Ended
	Dec. 31, 2017 $ / shares shares
Restricted Stock
Number of Shares
Unvested, beginning balance (in shares) | shares	22,150
Vested (in shares) | shares	(17,720)
Unvested, ending balance (in shares) | shares	4,430
Weighted-Average Grant Date Fair Value
Unvested beginning balance (in dollars per share) | $ / shares	$ 11.43
Vested (in dollars per share) | $ / shares	11.43
Unvested ending balance (in dollars per share) | $ / shares	$ 11.43
Restricted Stock Units (RSUs)
Number of Shares
Unvested, beginning balance (in shares) | shares	3,333
Vested (in shares) | shares	(3,333)
Unvested, ending balance (in shares) | shares	0
Weighted-Average Grant Date Fair Value
Unvested beginning balance (in dollars per share) | $ / shares	$ 4.09
Vested (in dollars per share) | $ / shares	4.09
Unvested ending balance (in dollars per share) | $ / shares	$ 0.00