Depreciation and amortization expense associated with certain businesses in our Health and Well-Being Services segment delivering benefits to our members, primarily associated with our pharmacy operations are included with benefits expense.

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- Definition

Percentage of collateral to fair value of investment securities on loan

+ Details

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- Definition

Percent of consolidated premiums and ASO fees related to long-duration insurance products

+ Details

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- Definition

The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ Details

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- Definition

The minimum useful life of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ Details

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Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Percent of consolidated premiums and ASO fees related to long-duration insurance products	2.00%
Depreciation and amortization expense	$ 18.1	$ 12.9	$ 10.0
Securities Lending Program [Member]
Percentage of collateral to fair value of investment securities on loan	102.00%
Building [Member]
Useful life, minimum years	20
Useful life, maximum years	40
Equipment [Member]
Useful life, minimum years	3
Useful life, maximum years	10
Computer Software [Member]
Useful life, minimum years	3
Useful life, maximum years	7