Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2020		Dec. 31, 2019
Fixed maturity securities, available for sale, amortized cost	$ 47,254,063	[1]	$ 48,238,946
Fixed maturity securities, available for sale, allowance for credit losses	28,332
Mortgage loans on real estate, allowance for credit losses	19,776		9,179
Coinsurance deposits, allowance for credit losses	$ 4,559		$ 0
Stockholders' equity:
Preferred stock, par value (dollars per share)	$ 1		$ 1
Preferred stock, aggregate liquidation preference	$ 400,000		$ 400,000
Preferred stock, shares authorized	2,000,000		2,000,000
Preferred stock, shares issued	16,000		16,000
Preferred stock, shares outstanding	16,000		16,000
Common stock, par value (dollars per share)	$ 1		$ 1
Common stock, shares authorized	200,000,000		200,000,000
Common stock, shares issued	91,497,841		91,107,555
Common stock, shares outstanding	91,497,841		91,107,555
Common stock, shares held in treasury	1,207,201		1,344,193

[1] (1) Amortized cost excludes accrued interest receivable of $456.1 million as of March 31, 2020.