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Business Acquisition, related premium credits to eligible policyholders.

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Third Party Conversion Agent Asset

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Amount of cash paid to acquire the entity.

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The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

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Fair value of noncash consideration given by the acquirer to acquire the entity. Does not include cash paid, the fair value of debt and securities issued and liabilities incurred to acquire the entity.

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Percentage of voting equity interests acquired in the business combination.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of other decrease (increase) in the carrying value of goodwill that is not separately disclosed.

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The number of businesses acquired by the entity during the period.

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Acquisitions (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Business	Dec. 31, 2011 APS [Member]	Dec. 31, 2010 APS [Member]	Nov. 30, 2010 APS [Member]	Dec. 27, 2012 Medmarc [Member]	Jan. 02, 2013 Medmarc [Member] Subsequent Event [Member]
Acquisitions (Textual) [Abstract]
Number of acquisitions acquired	0
Percentage of shares acquired				100.00%
Business acquisition, purchase price				$ 237
Business acquisition cash paid				233.0		153.7
Deferred compensation commitments				4
Expenses related to the purchase of business			2
Reduction in amount of goodwill related to purchase of APS		1.8
Goodwill recognized for the acquisition		37.3
Revenue of aquiree since acquisition date			6.2
Earnings of acquiree since acquisition date			1.0
Business acquisition, related premium credits to eligible policyholders						7.5
Third party conversion agent asset					$ 153.7