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Comprehensive Income (AOCI Rollforward) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | $ 1,861,751,660 | $ 2,049,518,261 | $ 1,910,424,234
Other comprehensive income (loss), net of tax | 311,235 | (2,150,994) | 8,464,688
Ending balance | 1,938,087,820 | 1,861,751,660 | 2,049,518,261
Accumulated Other Comprehensive Income (Loss) |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | (1,600,338) | 7,193,383 | (1,271,305)
Ending balance | (1,289,103) | (1,600,338) | 7,193,383
Foreign currency translation adjustments |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | (1,674,887) | 645,030 | (2,862,999)
Other comprehensive income before reclassifications | (709,702) | (2,319,917) | 3,508,029
Other comprehensive income (loss), net of tax | (709,702) | (2,319,917) | 3,508,029
Ending balance | (2,384,589) | (1,674,887) | 645,030
Unrealized gains(losses) on available-for-sale securities |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | 74,549 | 6,626,379 | 2,788,975
ASU 2016-01 adoption impact | 0 | (6,642,727) | 0
Other comprehensive income before reclassifications | 1,403,521 | 1,675,823 | 4,444,360
Amounts reclassified from accumulated other comprehensive income | (382,584) | (1,584,926) | (606,956)
Other comprehensive income (loss), net of tax | 1,020,937 | (6,551,830) | 3,837,404
Ending balance | 1,095,486 | 74,549 | 6,626,379
Unrealized gains (losses) on derivatives |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Beginning balance | 0 | (78,026) | (1,197,281)
Other comprehensive income before reclassifications | 0 | 175,308 | 248,042
Amounts reclassified from accumulated other comprehensive income | 0 | (97,282) | 871,213
Other comprehensive income (loss), net of tax | 0 | 78,026 | 1,119,255
Ending balance | $ 0 | $ 0 | $ (78,026)

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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