Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 20,578	$ 20,718
Adjustments to reconcile net income to net cash provided by operating activities:
FHLB stock dividends	(2,939)	(3,152)
Amortization and accretion of premiums and discounts on securities	1,362	1,289
Depreciation and amortization of premises and equipment	1,891	1,706
Amortization of deferred amounts related to FHLB advances, net	365	751
Common stock committed to be released for allocation - ESOP	634	525
Stock-based compensation	157	533
Changes in:
Other assets, net	(437)	83
Income taxes payable/receivable	8,899	9,226
Accounts payable and accrued expenses	(3,556)	(5,514)
Net cash provided by operating activities	26,954	26,165
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of AFS securities	(35,890)	0
Purchase of HTM securities	0	(1,432)
Proceeds from calls, maturities and principal reductions of AFS securities	61,274	116,678
Proceeds from calls, maturities and principal reductions of HTM securities	77,309	71,312
Proceeds from the redemption of FHLB stock	98,950	94,500
Purchase of FHLB stock	(91,405)	(59,832)
Net increase in loans receivable	(114,245)	(41,994)
Purchase of premises and equipment	(1,981)	(4,555)
Proceeds from sale of other real estate owned (OREO)	1,272	815
Net cash (used in) provided by investing activities	(4,716)	175,492
CASH FLOWS FROM FINANCING ACTIVITIES:
Dividends paid	(50,198)	(44,551)
Net change in deposits	28,656	139,960
Proceeds from borrowings	2,100,000	1,500,000
Repayments on borrowings	(2,200,000)	(2,300,000)
Change in advance payments by borrowers for taxes and insurance	(37,240)	(37,502)
Stock options exercised	5,147	158
Excess tax benefits from stock options	193	0
Net cash used in financing activities	(153,442)	(741,935)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(131,204)	(540,278)
CASH AND CASH EQUIVALENTS:
Beginning of period	281,764	772,632
End of period	150,560	232,354
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Income tax payments	5	13
Interest payments	$ 29,016	$ 25,686