Debt

We generally issue senior unsecured notes for long-term borrowing purposes. At March 31, 2014, we had $12,699.2 outstanding under these notes. During the three months ended March 31, 2014, we repurchased $21.2 of outstanding principal balance of certain senior unsecured notes, plus applicable premium for early redemption plus accrued and unpaid interest, for cash totaling $24.2. We recognized a loss on extinguishment of debt of $3.0 for the repurchase of these notes.

We have an unsecured surplus note with an outstanding principal balance of $24.9 at March 31, 2014.

We have a senior revolving credit facility, or the Facility, with certain lenders for general corporate purposes. The Facility, as amended, provides credit up to $2,000.0, and matures on September 29, 2016. There were no amounts outstanding under this Facility as of March 31, 2014 or at any time during the three months then ended.

We have an authorized commercial paper program of up to $2,500.0, the proceeds of which may be used for general corporate purposes. At March 31, 2014, we had $758.6 outstanding under this program.

We have issued senior convertible debentures due 2042, or the Debentures, which are governed by an indenture between us and The Bank of New York Mellon Trust Company, N.A., as trustee. We have accounted for the Debentures in accordance with the cash conversion guidance in FASB guidance for debt with conversion and other options. As a result, the value of the embedded conversion option has been bifurcated from its debt host and recorded as a component of “additional paid-in capital” (net of deferred taxes and equity issuance costs) in our consolidated balance sheets. The following table summarizes at March 31, 2014 the related balances, conversion rate and conversion price of the Debentures:




Outstanding principal amount	$	1,500.0
Unamortized debt discount	531.9
Net debt carrying amount	968.1
Equity component carrying amount	543.6
Conversion rate (shares of common stock per $1,000 of principal amount)	13.3135
Effective conversion price (per $1,000 of principal amount)	$	75.1113