Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fixed maturities, available for sale, amortized cost	$ 15,988,228	$ 15,753,471
Long-term debt, fair value	$ 1,458,751	$ 1,384,455
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)	121,218,183	121,218,183
Common stock, shares outstanding (in shares)	121,218,183	121,218,183
Common stock, shares held in treasury (in shares)	11,292,000	10,525,147
Fair Value Option [Member]
Fair value option	$ 118,556	$ 108,241
Partnership Interest [Member] \| Fair Value Option [Member]
Fair value option	$ 118,556	$ 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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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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