CONSOLIDATED BALANCE SHEETS PARENTHETICAL (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Available for Sale at Fair value - Amortized cost	$ 23,105,597	$ 20,270,734
Preferred stock par value	$ 0.01	$ 0.01
Preferred stock shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock par value	$ 0.01	$ 0.01
Common stock shares authorized	140,000,000us-gaap_CommonStockSharesAuthorized	140,000,000us-gaap_CommonStockSharesAuthorized
Common stock shares issued	79,137,758us-gaap_CommonStockSharesIssued	79,137,758us-gaap_CommonStockSharesIssued
Common stock shares outstanding	68,772,961us-gaap_CommonStockSharesOutstanding	70,768,218us-gaap_CommonStockSharesOutstanding
Treasury Shares Held	10,364,797us-gaap_TreasuryStockNumberOfSharesHeld	8,369,540us-gaap_TreasuryStockNumberOfSharesHeld
Allowances for Loan and Lease Losses, Real Estate	$ 6,471	$ 10,106

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.

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