Derivative and Hedging Activities (Tables)

12 Months Ended

Sep. 30, 2016

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Fair value of financial instruments by balance sheet grouping

Although management is not aware of any factors that would materially affect the estimated fair value amounts presented below, such amounts have not been comprehensively revalued for purposes of these financial statements since the dates shown, and therefore, estimates of fair value subsequent to those dates may differ significantly from the amounts presented below.

		September 30, 2016				September 30, 2015
	Level	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
		(In thousands)
Financial assets
Cash and cash equivalents	1	$	450,368	$	450,368	$	284,049	$	284,049
Available-for-sale securities:
Equity securities	1	101,824		101,824		101,952		101,952
U.S. government and agency securities	2	259,351		259,351		482,464		482,464
Municipal bonds	2	27,670		27,670		27,123		27,123
Corporate debt securities	2	461,138		461,138		505,800		505,800
Mortgage-backed securities
Agency pass-through certificates	2	993,041		993,041		1,160,518		1,160,518
Commercial MBS	2	79,870		79,870		102,706		102,706
Total available-for-sale securities		1,922,894		1,922,894		2,380,563		2,380,563
Held-to-maturity securities:
Mortgage-backed securities
Agency pass-through certificates	2	1,417,599		1,441,556		1,643,216		1,637,420
Total held-to-maturity securities		1,417,599		1,441,556		1,643,216		1,637,420
Loans receivable	3	9,910,920		10,414,794		9,170,634		9,667,750
FDIC indemnification asset	3	12,769		12,095		16,275		15,522
FHLB and FRB stock	2	117,205		117,205		107,198		107,198
Other assets - interest rate contracts	2	20,895		20,895		11,879		11,879
Financial liabilities
Customer accounts	2	10,600,852		10,184,321		10,631,703		10,004,290
FHLB advances and other borrowings	2	2,080,000		2,184,671		1,830,000		1,938,384
Other liabilities - interest rate contracts	2	20,895		20,895		11,879		11,879
Other liabilities - commercial loan hedges	2	3,312		3,312		966		966
Other liabilities - long term borrowing hedges	2	31,347		31,347		14,555		14,555

The following table presents the fair value and balance sheet classification of derivatives outstanding.

	Asset Derivatives						Liability Derivatives
	September 30, 2016			September 30, 2015			September 30, 2016			September 30, 2015
(In thousands)	Balance Sheet	Fair Value		Balance Sheet	Fair Value		Balance Sheet	Fair Value		Balance Sheet	Fair Value
Interest rate contracts	Other assets	$	20,895	Other assets	$	11,879	Other liabilities	$	20,895	Other liabilities	$	11,879
Commercial loan hedges	Other assets	—		Other assets	—		Other liabilities	3,312		Other liabilities	966
Long term borrowing hedges	Other assets	—		Other assets	—		Other liabilities	31,347		Other liabilities	14,555
		$	20,895		$	11,879		$	55,554		$	27,400