Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fixed maturities, available for sale, amortized cost	$ 15,984,272	$ 15,753,471
Other long-term investments under fair value option	289,147	207,258
Long-term debt, fair value	$ 1,446,082	$ 1,384,455
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized	320,000,000	320,000,000
Common stock, shares issued	121,218,183	121,218,183
Common stock, shares outstanding	121,218,183	121,218,183
Common stock, shares held in treasury	11,995,233	10,525,147
Partnership Interest - Fair Value Option \| Investment in limited partnerships
Other long-term investments under fair value option	$ 165,426	$ 108,241

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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