Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 113,450,870	$ 89,505,801
Other comprehensive income (loss) before tax:
Foreign currency translation adjustments	(852,412)	(692,090)
Unrealized (losses) gains on debt securities, net	(5,118,953)	2,779,730
Other comprehensive income (loss), before tax	(5,971,365)	2,087,640
Income tax impact related to components of other comprehensive income (loss)	(1,074,980)	583,743
Other comprehensive income (loss), net of tax	(4,896,385)	1,503,897
Comprehensive income	$ 108,554,485	$ 91,009,698