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v3.8.0.1

Condensed Parent Company Financial Statements (Condensed Balance Sheet) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Current assets: |  |  |  |
Other | $ 87.7 | $ 95.5 |  |
Total current assets | 905.1 | 877.1 |  |
Investments: |  |  |  |
Other | 121.9 | 20.0 |  |
Total investments | 396.1 | 337.6 |  |
Other assets | 69.7 | 22.6 |  |
Total assets | 14,187.8 | 13,373.8 | $ 12,495.2 |
Current liabilities: |  |  |  |
Commercial paper | 320.2 | 244.1 |  |
Other | 260.8 | 281.8 |  |
Total current liabilities | 2,149.0 | 1,162.0 |  |
Other liabilities | 306.4 | 279.3 |  |
Common Equity: |  |  |  |
Retained earnings | 2,346.0 | 2,177.0 |  |
Shares in deferred compensation trust | (11.1) | (10.0) |  |
Total common equity | 4,182.2 | 3,862.0 | $ 3,724.1 | $ 3,438.7
Total liabilities and equity | 14,187.8 | 13,373.8 |  |
Parent Company [Member] |  |  |  |
Current assets: |  |  |  |
Notes receivable from affiliated companies | 50.0 | 74.0 |  |
Other | 7.0 | 5.0 |  |
Total current assets | 57.0 | 79.0 |  |
Investments: |  |  |  |
Investments in consolidated subsidiaries | 4,676.0 | 4,211.0 |  |
Other | 2.0 | 2.0 |  |
Total investments | 4,678.0 | 4,213.0 |  |
Other assets | 78.0 | 64.0 |  |
Total assets | 4,813.0 | 4,356.0 |  |
Current liabilities: |  |  |  |
Commercial paper | 295.0 | 192.0 |  |
Notes payable to affiliated companies | 305.0 | 275.0 |  |
Other | 12.0 | 12.0 |  |
Total current liabilities | 612.0 | 479.0 |  |
Other liabilities | 20.0 | 18.0 |  |
Common Equity: |  |  |  |
Common stock and additional paid-in capital | 1,848.0 | 1,695.0 |  |
Retained earnings | 2,344.0 | 2,174.0 |  |
Shares in deferred compensation trust | (11.0) | (10.0) |  |
Total common equity | 4,181.0 | 3,859.0 |  |
Total liabilities and equity | $ 4,813.0 | $ 4,356.0 |  |

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