STOCK-BASED COMPENSATION - PERFORMANCE SHARES AND RESTRICTED STOCK ACTIVITY (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2016		Nov. 13, 2018	Nov. 14, 2017	Nov. 15, 2016
Performance share awards
Shares
Outstanding at beginning of period (in shares)	[1]	156,587		179,916		214,464
Granted (in shares)	[1]	91,177		96,507		115,480
Vested (in shares)	[1]	(100,146)	[2]	(95,407)	[3]	(137,053)	[4]
Cancelled/forfeited (in shares)	[1]	(2,442)		(24,429)		(12,975)	[5]
Outstanding at end of period (in shares)	[1]	145,176		156,587		179,916
Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)		$ 30.12		$ 27.47		$ 23.40
Granted (in dollars per share)		44.67		33.57		27.37
Vested (in dollars per share)		29.49	[2]	28.88	[3]	21.40	[4]
Cancelled/forfeited (in dollars per share)		31.45		29.14		23.40	[5]
Outstanding at end of period (in dollars per share)		$ 39.67		$ 30.12		$ 27.47
Total Fair Value of Vested Shares		$ 4,714	[2]	$ 4,179	[3]	$ 5,657	[4]
Percent of awards to common stock									100.00%	150.00%
Number of common shared issued (in shares)									36,498.49	71,808
Percent of awards to common stock, target									119.00%	100.00%
Performance share awards | Minimum
Weighted Average Grant Date Fair Value
Percent of awards to common stock		0.00%
Performance share awards | Maximum
Weighted Average Grant Date Fair Value
Percent of awards to common stock		150.00%
Performance Shares, Subject to Performance Conditions
Shares
Outstanding at beginning of period (in shares)		51,931		69,305
Outstanding at end of period (in shares)		59,341		51,931		69,305
Weighted Average Grant Date Fair Value
Percent of awards to common stock										85.00%
Number of common shared issued (in shares)										55,702.2
Number of shares canceled (in shares)										9,366
Performance-based Restricted Stock
Weighted Average Grant Date Fair Value
Percent of awards to common stock									100.00%	100.00%
Number of common shared issued (in shares)									28,223	23,649
Performance Shares, TSR
Weighted Average Grant Date Fair Value
Percent of awards to common stock									108.44%
Number of common shared issued (in shares)									39,594.6972
Restricted Stock
Shares
Outstanding at beginning of period (in shares)		51,154		73,071		81,492
Granted (in shares)		27,949		28,734		41,909
Vested (in shares)		(33,815)		(38,752)		(48,089)
Cancelled/forfeited (in shares)		(1,120)		(11,899)		(2,241)
Outstanding at end of period (in shares)		44,168		51,154		73,071
Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)		$ 32.40		$ 29.09		$ 27.17
Granted (in dollars per share)		45.00		35.79		30.03
Vested (in dollars per share)		31.23		28.92		26.66
Cancelled/forfeited (in dollars per share)		33.54		31.56		29.21
Outstanding at end of period (in dollars per share)		$ 41.24		$ 32.40		$ 29.09
Total Fair Value of Vested Shares		$ 1,438		$ 1,344		$ 1,469
Subsequent Event | Performance share awards
Weighted Average Grant Date Fair Value
Percent of awards to common stock								120.50%
Number of common shared issued (in shares)								39,694.05
Percent of awards to common stock, target								100.00%
Subsequent Event | Performance-based Restricted Stock
Weighted Average Grant Date Fair Value
Percent of awards to common stock								100.00%
Number of common shared issued (in shares)								36,998
Subsequent Event | Performance Shares, TSR
Weighted Average Grant Date Fair Value
Percent of awards to common stock								99.00%
Number of common shared issued (in shares)								38,660.49

[1] The number of common shares issued related to certain performance shares may range from zero to 150 percent of the number of shares shown in the table above based on the Company’s achievement of performance goals.

[2] As certified by the Company’s Leadership and Compensation Committee on November 13, 2018, the number of common shares earned related to TSR performance was 99 percent or 38,660 shares, the number of common shares earned related to NFE performance was 121 percent or 39,694 shares and the number of common shares earned related to Performance Based Restricted Stock was 100 percent or 36,998 shares. Each award earned excludes accumulated dividends. The number represented on this line is the target number of 100 percent.

[3] As certified by the Company’s Leadership and Compensation Committee on November 14, 2017, the number of common shares earned related to TSR performance was 108.44 percent or 39,595 shares, the number of common shares earned related to NFE performance was 119 percent or 36,498 shares, and the number of common shares earned related to Performance Based Restricted Stock was 100 percent or 28,223 shares. Each award earned excludes accumulated dividends. The number represented on this line is the target number of 100 percent.

[4] As certified by the Company’s Leadership and Compensation Committee on November 15, 2016, the number of common shares related to performance shares earned was 85 percent, or 55,702 shares, the number of common shares earned related to NFE performance was 150 percent or 71,808 shares, and the number of common shares earned related to Performance Based Restricted Stock was 100 percent or 23,649 shares. Each award earned excludes accumulated dividends. The number represented on this line is the target number of 100 percent.

[5] As certified by the Company’s Leadership and Compensation Committee on November 15, 2016, 9,366 shares were canceled due to not achieving a certain performance target. The remainder were forfeitures due to individuals departing the Company.