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Income Taxes (ASC 740-10) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Mar. 31, 2014
Income Tax Contingency [Line Items] |  |  |  |  |  |  |
Percentage of likelihood for realization of benefit upon ultimate settlement |  |  | 50.00% |  |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |  |  |  |  |
Balance at beginning | $ 46.6 |  | $ 65.5 |  | $ 95.8 |  |
Changes in prior year tax positions | (4.8) |  | 1.9 |  | 1.2 |  |
Tax positions taken during the current year | 8.6 |  |  |  |  |  |
Lapse in statute of limitations |  |  |  |  | (10.5) |  |
Settlements with tax authorities | (0.4) |  | (0.6) |  | (0.6) |  |
Tax positions taken during the current year |  |  | (20.2) |  | (20.4) |  |
Balance at year end | 50.0 |  | 46.6 |  | 65.5 |  |
Unrecognized tax benefit recognition including interest and penalties, if recognized, would effect income tax expense | 27.5 |  |  |  |  |  | 5.0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound | 5.2 |  |  |  |  |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | 1.3 |  | 1.2 |  | 0.6 |  |
Permanent Differences [Member] |  |  |  |  |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |  |  |  |  |
Balance at beginning | 9.7 | [1] | 9.6 | [1] | 14.5 | [1] |
Changes in prior year tax positions | 0.6 | [1] | 0.5 | [1] | (0.9) | [1] |
Tax positions taken during the current year | 7.9 | [1] |  |  |  |  |
Lapse in statute of limitations |  |  |  |  | (3.4) | [1] |
Settlements with tax authorities | 0 | [1] | (0.4) | [1] | (0.6) | [1] |
Tax positions taken during the current year |  |  | 0 | [1] | 0 | [1] |
Balance at year end | 18.2 | [1] | 9.7 | [1] | 9.6 | [1] |
Temporary Differences [Member] |  |  |  |  |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |  |  |  |  |
Balance at beginning | 28.9 | [2] | 49.1 | [2] | 75.1 | [2] |
Changes in prior year tax positions | (7.1) | [2] | 0 | [2] | 0.1 | [2] |
Tax positions taken during the current year | 0.7 | [2] |  |  |  |  |
Lapse in statute of limitations |  |  |  |  | (5.7) | [2] |
Settlements with tax authorities | 0 | [2] | 0 | [2] | 0 | [2] |
Tax positions taken during the current year |  |  | (20.2) | [2] | (20.4) | [2] |
Balance at year end | 22.5 | [2] | 28.9 | [2] | 49.1 | [2] |
Interest and Penalties Net of Tax Benefit [Member] |  |  |  |  |  |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns |  |  |  |  |  |  |
Balance at beginning | 8.0 | [3] | 6.8 | [3] | 6.2 | [3] |
Changes in prior year tax positions | 1.7 | [3] | 1.4 | [3] | 2.0 | [3] |
Tax positions taken during the current year | 0 | [3] |  |  |  |  |
Lapse in statute of limitations |  |  |  |  | (1.4) | [3] |
Settlements with tax authorities | (0.4) | [3] | (0.2) | [3] | 0 | [3] |
Tax positions taken during the current year |  |  | 0 | [3] | 0 | [3] |
Balance at year end | $ 9.3 | [3] | $ 8.0 | [3] | $ 6.8 | [3] |
[1] | Represents the amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate.
[2] | Represents the amount of unrecognized tax benefits that, if recognized would create a temporary difference between the reported amount of an item in the Company’s Consolidated Balance Sheet and its tax basis.
[3] | Net of tax benefit.

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- Definition The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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