Investments: Schedule of Available for sale Securities, Debt Maturities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Text Block [Abstract]
Due after one year through five years, Amortized Cost	$ 50,055
Due after five years through ten years, Amortized Cost	4,663
Due after ten years, Amortized Cost	14,407
Debt maturities, Amortized Cost	69,125
Mortgage-backed investments, Amortized Cost	81,600
Amortized Cost	150,725	127,701
Due after one year through five years, Fair Value	50,089
Due after five years through ten years, Fair Value	4,697
Due after ten years, Fair Value	14,399
Debt maturities, Fair Value	69,185
Mortgage-backed investments, Fair Value	83,077
Fair Value	$ 152,262

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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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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount of available-for-sale debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents securitized, pay-through debt securities collateralized by real estate mortgage loans (mortgages) as of the balance sheet date which have been categorized as available-for-sale.

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