DEBT (Narrative) (Details) - 6 months ended Jun. 30, 2019 $ in Millions	USD ($)	NZD ($)
Debt Instrument [Line Items]
Proceeds from lines of credit	$ 0
Total debt	975,000,000
Term Credit Agreement
Debt Instrument [Line Items]
Total debt	350,000,000
Revolving Credit Facility borrowings due 2020 \| Unsecured Revolving Credit Agreement Expiring 2020
Debt Instrument [Line Items]
Repayments of lines of credit	0
Remaining borrowing capacity	198,400,000
Maximum borrowing capacity	200,000,000
Working Capital Facility
Debt Instrument [Line Items]
Proceeds from lines of credit	0
Repayments of lines of credit	0
Remaining borrowing capacity		$ 20.0
Incremental Term Loan Agreement
Debt Instrument [Line Items]
Total debt	300,000,000
Standby Letters of Credit \| Revolving Credit Facility borrowings due 2020 \| Unsecured Revolving Credit Agreement Expiring 2020
Debt Instrument [Line Items]
Amount to secure outstanding letters of credit	$ 1,600,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Maximum borrowing capacity 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.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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