Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fixed maturities, available for sale, amortized cost	$ 16,371,944	$ 16,415,776
Fixed maturities, available for sale, allowance for credit losses	31,854	0
Other long-term investments under fair value option	377,239	326,347
Total long-term debt, fair value	$ 1,386,511	$ 1,473,364
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	320,000,000	320,000,000
Common stock, shares issued (in shares)	117,218,183	117,218,183
Common stock, shares outstanding (in shares)	117,218,183	117,218,183
Common stock, shares held in treasury (in shares)	10,783,915	9,497,940
Partnership Interest - Fair Value Option | Investment in limited partnerships
Other long-term investments under fair value option	$ 211,791	$ 185,851