v3.8.0.1

DEBT Narrative 1 (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Debt Instrument [Line Items] |  |  |  |
Interest payments |  | $ 163.6 | $ 146.1 | $ 138.9
Amortization of debt issuance costs and debt discount |  | $ 5.0 | $ 4.4 | $ 4.0
$1.75 billion revolving credit agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Maturity Date |  | Oct. 29, 2020 | Oct. 29, 2019 |
Maximum borrowing capacity |  | $ 1,750.0 | $ 1,500.0 |
Maximum available for Euro borrowings |  | 250.0 |  |
Maximum available for British Pound Borrowings |  | $ 250.0 |  |
Line of Credit Facility, Covenant Terms |  | maximum allowed consolidated debt coverage ratio (as defined in the Revolving Credit Agreement) from 5.00-to-1.00 to 5.50-to-1.00 through the rolling period ending March 31, 2018. Subsequently, the maximum allowed consolidated debt coverage ratio may not exceed 5.00-to-1.00 for any rolling period ending on or after June 30, 2018. If we complete one or more acquisitions for aggregate net consideration of at least $50.0 million, our maximum consolidated debt coverage ratio will increase to 5.50-to-1.00 for two rolling periods. On November 22, 2017, the Revolving Credit Agreement was amended to continue to exclude our $402.5 million fixed-to-floating rate subordinated notes from the definition of consolidated debt for purposes of calculating our consolidated debt coverage ratio through December 31, 2018. The Revolving Credit Agreement also contains customary restrictive covenants, such as limitations on indebtedness, liens, mergers, asset transfers and certain investing activities. |  |
Current remaining borrowing capacity |  | $ 853.0 |  |
Interest rate at period end |  | 3.20% |  |
Interest rate during period |  | 2.80% |  |
Letters of credit issued |  | $ 3.7 |  |
Maximum letters of credit allowed |  | 400.0 |  |
Line of Credit Facility, Maximum Letters of Credit Available for Euro Borrowings |  | 25.0 |  |
Line of Credit Facility, Maximum Letters of Credit Available for British Pound Borrowings |  | 25.0 |  |
Other long-term assets, net | $1.75 billion revolving credit agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Deferred issuance costs |  | $ 3.1 |  |
Subsequent Event [Member] | $1.75 billion revolving credit agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate increase | 0.25% |  |  |

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- Definition Amount of letters of credit issued under the credit facility as of the balance sheet date. + References No definition available. + Details
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- Definition Maximum borrowing capacity under the credit facility that is available for borrowings in Euros. + References No definition available. + Details
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- Definition Maximum amount of letters of credit that can be issued under the credit facility (without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility). + References No definition available. + Details
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- Definition Maximum borrowing capacity under the credit facility that is available for borrowings in British Pounds. + References No definition available. + Details
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- Definition Line of Credit Facility, Maximum Letters of Credit Available for Euro Borrowings + References No definition available. + Details
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- Definition Amount of amortization expense attributable to debt discount (premium) and debt issuance costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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- Definition Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of cash paid for interest. Includes, but is not limited to, payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585 + Details
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