STOCK-BASED COMPENSATION - Stock options (Details) - Stock options - $ / shares	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Common-stock based award plan
Option vesting rights (as a percent)	25.00%
Weighted-average assumptions utilized in determining the fair value of options
Risk-free interest rate (as a percent)	2.00%	1.80%	1.70%
Expected stock volatility (as a percent)	38.90%	37.60%	36.90%
Dividend yield (as a percent)	3.70%	4.60%	3.90%
Expected term (in years)	5 years 6 months	5 years 6 months	5 years 6 months
Weighted-average fair value of options granted (in dollars per share)	$ 20.48	$ 13.12	$ 16.39
Options
Options outstanding at the beginning of the period (in shares)	3,312,000	2,776,000	2,629,000
Granted (in shares)	396,007	876,000	420,000
Exercised (in shares)	(415,000)	(220,000)	(255,000)
Forfeited/Expired (in shares)	(15,000)	(120,000)	(18,000)
Option outstanding at the end of the period (in shares)	3,278,000	3,312,000	2,776,000
Exercisable at the end of the period (in shares)	2,167,000	2,225,000	2,014,000
Shares available to grant	5,624,000	6,600,000	2,515,000
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 51.74	$ 48.51	$ 43.46
Granted (in dollars per share)	76.61	58.25	68.83
Exercised (in dollars per share)	38.04	31.52	28.46
Forfeited/Expired (in dollars per share)	68.32	61.80	66.78
Outstanding at the end of the period (in dollars per share)	56.41	51.74	48.51
Exercisable at the end of the period (in dollars per share)	$ 50.87	$ 46.66	$ 41.62
Minimum
Common-stock based award plan
Vesting period	1 year
Maximum
Common-stock based award plan
Vesting period	4 years