FINANCING ARRANGEMENTS (Details) $ in Thousands, NZD in Millions, AUD in Millions				1 Months Ended	12 Months Ended
	Aug. 11, 2016 USD ($)	Feb. 02, 2016 USD ($)	Jul. 17, 2015 USD ($)	Mar. 31, 2013 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2016 NZD	Sep. 30, 2016 AUD	Sep. 30, 2016 USD ($)	Oct. 31, 2015 USD ($)
Financial arrangement
Long-term debt						$ 126,705				$ 201,012
Less current portion						(525)				(450)
Long-term Debt, Excluding Current Maturities						126,180				200,562
Maturities of long-term debt
2017										500
2018										500
2019										100
2020										10,700
2021										35,700
Amount of interest paid					$ 11,000	4,800	$ 4,100
Short term borrowings
Debt issuance costs incurred					$ 3,647
Maximum distrutions to shareholders										48,700
Self-insurance liabilities						$ 8,800				8,200
Letters of credit primarily for self-insured liabilities
Short term borrowings
Letters of Credit and bank guarantees outstanding										16,600
Fair value of instruments										0
Letters of credit and bank guarantees
Short term borrowings
Letters of Credit and bank guarantees outstanding										79,200
New Zealand
Short term borrowings
Maximum borrowing capacity under credit agreement								NZD 0.5		400
Borrowings outstanding										0
Australia
Short term borrowings
Maximum borrowing capacity under credit agreement									AUD 3.0	2,300
Borrowings outstanding										$ 0
Senior unsecured notes
Financial arrangement
Interest rate (as a percent)		3.93%	3.70%	3.35%
Maturities of long-term debt
Additional senior notes principal amount agreed to be issued		$ 75,000	$ 25,000	$ 100,000
Series A senior unsecured notes
Financial arrangement
Interest rate (as a percent)						3.35%		3.35%	3.35%	3.35%
Long-term debt						$ 50,000				$ 50,000
Series B senior unsecured notes
Financial arrangement
Interest rate (as a percent)						3.35%		3.35%	3.35%	3.35%
Long-term debt						$ 50,000				$ 50,000
Series C senior unsecured notes
Financial arrangement
Interest rate (as a percent)						3.70%		3.70%	3.70%	3.70%
Long-term debt						$ 25,000				$ 25,000
Series D senior unsecured notes
Financial arrangement
Interest rate (as a percent)								3.93%	3.93%	3.93%
Long-term debt										$ 75,000
Mortgage notes | United Kingdom
Financial arrangement
Interest rate (as a percent)						6.48%		6.48%	6.48%	6.48%
Long-term debt						$ 1,705				$ 1,012
Revolving credit agreement
Short term borrowings
Maximum borrowing capacity under credit agreement		400,000									$ 200,000
Amount borrowed		150,000
Borrowings outstanding										240,000
Letters of credit outstanding										20,700
Available amount under line of credit										$ 139,300
Weighted average interest rate on outstanding borrowings								2.50%	2.50%	2.50%
Debt issuance costs incurred	$ 1,300	$ 2,300
Unamortized debt issuance costs										$ 2,900
Secured letter of credit agreement
Short term borrowings
Maximum borrowing capacity under credit agreement										63,100
Letters of credit outstanding										62,700
Secured letter of credit agreement | United Kingdom
Short term borrowings
Cash on deposit as collateral										$ 69,400