CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Amortized cost	$ 2,374,816	$ 2,130,029
Common stock, par value
Common stock, authorized	225,000,000	225,000,000
Common stock, shares issued	104,889,586	104,482,271
Common stock, shares outstanding	104,889,586	104,482,271

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.

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