INVESTMENT SECURITIES (net gains on trading account securities) (Detail) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Net realized gain on sales	$ 43	$ 229	$ 795
Net unrealized loss on securities held as of the balance sheet date	0	(29)	(47)
Net gain on trading account securities	$ 43	$ 200	$ 748

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

No definition available.

Name:	us-gaap_TradingSecuritiesUnrealizedHoldingGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration