Share-Based Compensation - Summary of Option Activity Under 2013 Plan (Details) - Option Activity Under the 2013 Plan $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Shares
Outstanding, beginning of year (in shares) | shares	316,777
Granted (in shares) | shares	0
Exercised (in shares) | shares	(11,415)
Forfeited (in shares) | shares	0
Outstanding, end of year (in shares) | shares	305,362
Exercisable, end of year (in shares) | shares	271,763
Weighted– Average Exercise Price
Outstanding, beginning of year (in dollars per share) | $ / shares	$ 12.99
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	10.38
Forfeited (in dollars per share) | $ / shares	0
Outstanding, end of year (in dollars per share) | $ / shares	13.09
Exercisable, end of year (in dollars per share) | $ / shares	$ 12.52
Outstanding, Weighted Average Remaining Contractual Term	5 years 4 months 17 days
Exercisable, Weighted Average Remaining Contractual Term	5 years 21 days
Outstanding, Aggregate Intrinsic Value | $	$ 846,973
Exercisable, Aggregate Intrinsic Value | $	$ 908,827