Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Net income	$ 7,360,515	$ 2,531,688
Reversal of net unrealized gain on sale of securities		(236,439)
Unrealized gain on bond purchase commitments	220,944	1,587,813
Comprehensive income	26,561,825	16,220,489
Comprehensive income (loss) allocated to noncontrolling interest	71,653	(12)
Partnership comprehensive income	26,490,172	16,220,501
Accumulated Other Comprehensive Income (Loss) [Member]
Net income	7,360,515	2,531,688
Reversal of net unrealized gain on sale of securities		(236,439)
Unrealized gain on securities	18,980,366	12,337,427
Unrealized gain on bond purchase commitments	220,944	1,587,813
Commitments [Member] \| Accumulated Other Comprehensive Income (Loss) [Member]
Unrealized gain on bond purchase commitments	$ 220,944	$ 1,587,813

Reversal of net unrealized gain on sale of securities.

No definition available.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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