Acquisitions - impact of equity transactions (Details) - Alliance Boots $ in Millions	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Consideration attributed to WBAD	$ 2,559
Less: carrying value of the Company’s pre-existing noncontrolling interest	130
Impact to additional paid in capital	$ 2,429

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

No definition available.

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