CONDENSED CONSOLIDATED BALANCE SHEETS PARENTHETICAL - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Available for Sale at Fair value - Amortized cost	$ 35,913,705	$ 35,281,412
Preferred stock par value (per share)	$ 0.01	$ 0.01
Preferred stock shares authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common stock par value (per share)	$ 0.01	$ 0.01
Common stock shares authorized	140,000,000	140,000,000
Common Stock, Shares, Issued	79,137,758	79,137,758
Common stock shares outstanding	64,512,773	64,452,095
Treasury stock, shares	14,624,985	14,685,663
Allowance for Loan and Lease Losses, Real Estate	$ 8,864	$ 9,384
Available-for-sale Equity Securities, Amortized Cost Basis	$ 110,747	$ 102,841

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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