BUSINESS SEGMENTS (Details 2) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014		Dec. 31, 2014
Segment Reporting Information
Interest income		$ 264,632	$ 285,948		$ 783,338	$ 866,563
Charge for funds used		(82,727)	(75,812)		(226,230)	(204,373)
Interest spread on funds used		181,905	210,136		557,108	662,190
Interest expense		(24,343)	(28,974)		(79,840)	(85,173)
Credit on funds provided		82,727	75,812		226,230	204,373
Interest spread on funds provided		58,384	46,838		146,390	119,200
Net interest income before provision for credit losses		240,289	256,974		703,498	781,390
Provision for credit losses		7,736	15,225		16,217	30,158
Depreciation, amortization and accretion		7,096	38,893		17,341	62,914
Goodwill		469,433	458,467		469,433	458,467		$ 469,433
Segment pre-tax profit (loss)	[1]	138,989	85,299		430,236	324,428
Segment assets	[1]	31,119,676	28,484,169		31,119,676	28,484,169		$ 28,743,592
Retail Banking
Segment Reporting Information
Interest income		81,911	95,911		252,085	294,428
Charge for funds used		(20,795)	(24,738)		(65,452)	(72,888)
Interest spread on funds used		61,116	71,173		186,633	221,540
Interest expense		(13,727)	(12,057)		(38,946)	(35,718)
Credit on funds provided		68,783	60,770		187,401	163,102
Interest spread on funds provided		55,056	48,713		148,455	127,384
Net interest income before provision for credit losses		116,172	119,886		335,088	348,924
Provision for credit losses		1,455	394		(1,268)	2,606
Depreciation, amortization and accretion		1,827	4,806		6,743	11,473
Goodwill		357,207	354,163		357,207	354,163
Segment pre-tax profit (loss)		52,325	45,163	[1]	160,609	138,518	[1]
Segment assets		7,274,494	7,775,343	[1]	7,274,494	7,775,343	[1]
Commercial Banking
Segment Reporting Information
Interest income		166,693	175,032		482,816	525,987
Charge for funds used		(41,447)	(35,809)		(117,125)	(101,907)
Interest spread on funds used		125,246	139,223		365,691	424,080
Interest expense		(4,765)	(4,692)		(13,738)	(11,393)
Credit on funds provided		8,849	9,908		24,859	27,328
Interest spread on funds provided		4,084	5,216		11,121	15,935
Net interest income before provision for credit losses		129,330	144,439		376,812	440,015
Provision for credit losses		6,281	14,831		17,485	27,552
Depreciation, amortization and accretion		(13,496)	(412)		(30,027)	(5,026)
Goodwill		112,226	104,304		112,226	104,304
Segment pre-tax profit (loss)		96,605	49,364	[1]	287,049	204,134	[1]
Segment assets		17,125,065	14,879,699	[1]	17,125,065	14,879,699	[1]
Other
Segment Reporting Information
Interest income		16,028	15,005		48,437	46,148
Charge for funds used		(20,485)	(15,265)		(43,653)	(29,578)
Interest spread on funds used		(4,457)	(260)		4,784	16,570
Interest expense		(5,851)	(12,225)		(27,156)	(38,062)
Credit on funds provided		5,095	5,134		13,970	13,943
Interest spread on funds provided		(756)	(7,091)		(13,186)	(24,119)
Net interest income before provision for credit losses		(5,213)	(7,351)		(8,402)	(7,549)
Provision for credit losses		0	0		0	0
Depreciation, amortization and accretion		18,765	34,499		40,625	56,467
Goodwill		0	0		0	0
Segment pre-tax profit (loss)		(9,941)	(9,228)	[1]	(17,422)	(18,224)	[1]
Segment assets		$ 6,720,117	$ 5,829,127	[1]	$ 6,720,117	$ 5,829,127	[1]

[1] Prior periods were restated to reflect the retrospective application of adopting the new accounting guidance related to the Company’s investments in qualified affordable housing projects Accounting Standards Update (“ASU”) 2014-01. See Note 10 — Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net to the Consolidated Financial Statements for additional information.