Employee Benefits (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure [Line Items]
Maximum annual contribution per employee, percent	100.00%
Minimum annual contribution per employee, percent	1.00%
Maximum annual contribution per employee	$ 18,500	$ 18,000	$ 18,000
Cost recognized	358,167	311,467	228,619
Catchup Contribution Max
Defined Contribution Plan Disclosure [Line Items]
Maximum annual contribution per employee	$ 6,000	$ 6,000	$ 6,000
Tranche one
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Percentage of participant contribution	3.00%
Tranche two
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match	50.00%
Percentage of participant contribution	2.00%

Amount of cost for defined contribution plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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