Our notes payable, capital leases and long-term debt as of March 31, 2013 and December 31, 2012 are listed in the following table in millions, and are presented net of unamortized discounts and the unamortized portion of adjustments to fair value recorded in purchase accounting. Original issue discounts and adjustments to fair value recorded in purchase accounting are amortized to interest expense over the term of the applicable instrument using the effective interest method. | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | March 31, 2013 | | December 31, 2012 | Maturity | | Interest Rate | | Principal | | Discount | | Carry Value | | Principal | | Discount | | Carry Value | Credit facilities: | | | | | | | | | | | | | | | Uncommitted revolver | | Variable | | $ | — |
| | $ | — |
| | $ | — |
| | $ | 13.9 |
| | $ | — |
| | $ | 13.9 |
| April 2016 | | Variable | | — |
| | — |
| | — |
| | 25.0 |
| | — |
| | 25.0 |
| May 2017 | | Variable | | — |
| | — |
| | — |
| | — |
| | — |
| | — |
| Senior notes: | | | | | | | | | | | | | | | May 2018 | | 3.800 | | 700.0 |
| | (0.2 | ) | | 699.8 |
| | 700.0 |
| | (0.2 | ) | | 699.8 |
| September 2019 | | 5.500 | | 650.0 |
| | (3.3 | ) | | 646.7 |
| | 650.0 |
| | (3.4 | ) | | 646.6 |
| March 2020 | | 5.000 | | 850.0 |
| | (0.1 | ) | | 849.9 |
| | 850.0 |
| | (0.1 | ) | | 849.9 |
| November 2021 | | 5.250 | | 600.0 |
| | — |
| | 600.0 |
| | 600.0 |
| | — |
| | 600.0 |
| June 2022 | | 3.550 | | 850.0 |
| | (2.2 | ) | | 847.8 |
| | 850.0 |
| | (2.2 | ) | | 847.8 |
| May 2023 | | 4.750 | | 550.0 |
| | (1.3 | ) | | 548.7 |
| | 550.0 |
| | (1.3 | ) | | 548.7 |
| March 2035 | | 6.086 | | 275.7 |
| | (24.8 | ) | | 250.9 |
| | 275.7 |
| | (24.9 | ) | | 250.8 |
| March 2040 | | 6.200 | | 650.0 |
| | (0.5 | ) | | 649.5 |
| | 650.0 |
| | (0.5 | ) | | 649.5 |
| May 2041 | | 5.700 | | 600.0 |
| | (3.3 | ) | | 596.7 |
| | 600.0 |
| | (3.4 | ) | | 596.6 |
| Debentures: | | | | | | | | | | | | | | | May 2021 | | 9.250 | | 35.3 |
| | (1.8 | ) | | 33.5 |
| | 35.3 |
| | (1.9 | ) | | 33.4 |
| September 2035 | | 7.400 | | 165.3 |
| | (41.4 | ) | | 123.9 |
| | 165.2 |
| | (41.4 | ) | | 123.8 |
| Tax-exempt: | | | | | | | | | | | | | | | 2013 - 2035 | | 0.160 - 5.625 | | 1,096.7 |
| | (0.3 | ) | | 1,096.4 |
| | 1,097.9 |
| | (0.4 | ) | | 1,097.5 |
| Other: | | | | | | | | | | | | | | | 2013 - 2046 | | 5.000 - 11.900 | | 89.1 |
| | — |
| | 89.1 |
| | 87.2 |
| | — |
| | 87.2 |
| Total Debt | | | | $ | 7,112.1 |
| | $ | (79.2 | ) | | 7,032.9 |
| | $ | 7,150.2 |
| | $ | (79.7 | ) | | 7,070.5 |
| Less: Current portion | | | | | | | | (25.1 | ) | | | | | | (19.4 | ) | Long-term portion | | | | | | | | $ | 7,007.8 |
| | | | | | $ | 7,051.1 |
|
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