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DEBT (Schedule of Debt) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
DEBT (Schedule of Debt) (Details) - USD ($) $ in Thousands	Oct. 31, 2016	Apr. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Apr. 01, 2015
Debt Instrument [Line Items]
Debt Issuance Cost			$ 1,491	$ 1,586
Long-term debt
Long-term Debt and Capital Lease Obligations, Including Current Maturities			704,247	703,835
Less current portion			111	131
Long-term debt, less current portion			704,136	703,704
Short-term debt
Amounts due banks, interest at 31.8% (29.0% in 2016)			2,020	1,758
Current portion of long-term debt			111	131
Total short-term debt			2,131	1,889
Total debt			$ 706,267	$ 705,593
Short-term Debt, Weighted Average Interest Rate			31.80%	29.00%
Senior Notes 2015 [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate					3.50%
Debt Instrument, Face Amount					$ 350,000
Weighted Average [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	18 years	19 years	18 years
Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate			3.30%
Long-term debt
Long-term Debt and Capital Lease Obligations, Including Current Maturities			$ 693,424	$ 692,975
Other borrowings due through 2023, interest up to 8.0%
Long-term debt
Long-term Debt and Capital Lease Obligations, Including Current Maturities			$ 10,823	$ 10,860
Minimum
Short-term debt
Derivative, Variable Interest Rate			2.00%
Minimum \| Senior Notes 2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		10 years
Minimum \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			2.80%
Maximum
Short-term debt
Derivative, Variable Interest Rate			3.20%
Maximum \| Senior Notes 2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		30 years
Maximum \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.00%
Maximum \| Other borrowings due through 2023, interest up to 8.0%
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			8.00%
Senior Notes Series A [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 100,000
Debt Instrument, Maturity Date			Aug. 20, 2025
Debt Instrument, Interest Rate, Stated Percentage			3.15%
Senior Notes Series B [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 100,000
Debt Instrument, Maturity Date			Aug. 20, 2030
Debt Instrument, Interest Rate, Stated Percentage			3.35%
Senior Notes Series C [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 50,000
Debt Instrument, Maturity Date			Apr. 01, 2035
Debt Instrument, Interest Rate, Stated Percentage			3.61%
Senior Notes Series D [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 100,000
Debt Instrument, Maturity Date			Apr. 01, 2045
Debt Instrument, Interest Rate, Stated Percentage			4.02%
Designated as Hedging Instruments \| Interest Rate Swap [Member]
Short-term debt
Derivative, Notional Amount			$ 100,000