CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Interest receivable - consolidated trusts amount	$ 186,429,000	$ 199,195,000
Accrued interest payable - consolidated trusts amount	92,738,000	106,959,000
Available-for-Sale Securities
Amortized cost of available-for-sale investment securities	3,843,666,000	2,961,430,000
Farmer Mac Guaranteed Securities:
Amortized cost of available-for-sale investment securities	6,594,992,000	7,016,971,000
Consolidated VIEs:
Interest receivable - consolidated trusts amount	16,401,000	20,568,000
Accrued interest payable - consolidated trusts amount	$ 14,370,000	$ 18,018,000
Series A
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	2,400,000	2,400,000
Preferred stock, shares issued (in shares)	2,400,000	2,400,000
Preferred stock, shares outstanding (in shares)	2,400,000	2,400,000
Preferred stock, redemption amount	$ 60,000,000
Series C
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	3,000,000	3,000,000
Preferred stock, shares issued (in shares)	3,000,000	3,000,000
Preferred stock, shares outstanding (in shares)	3,000,000	3,000,000
Series D
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	4,000,000	4,000,000
Preferred stock, shares issued (in shares)	4,000,000	4,000,000
Preferred stock, shares outstanding (in shares)	4,000,000	4,000,000
Series E
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	3,180,000	3,180,000
Preferred stock, shares issued (in shares)	3,180,000	3,180,000
Preferred stock, shares outstanding (in shares)	3,180,000	3,180,000
Series F
Preferred stock, par value (in dollars per share)	$ 25	$ 25
Preferred stock, shares authorized (in shares)	4,800,000	4,800,000
Preferred stock, shares issued (in shares)	4,800,000	4,800,000
Preferred stock, shares outstanding (in shares)	4,800,000	4,800,000
Class A voting common stock
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares outstanding (in shares)	1,030,780	1,030,780
Class B voting common stock
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares outstanding (in shares)	500,301	500,301
Class C non-voting common stock
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares outstanding (in shares)	9,205,897	9,180,744

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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