Investment Securities (Summary Of Gross Unrealized Losses Not Considered OTTI) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013 holding		Dec. 31, 2012 holding
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	$ 1,346,853		$ 405,620
Available for sale, Unrealized Losses - Less Than Twelve Months	(38,389)		(1,436)
Available for sale, Fair Value - Twelve Months or Longer	85,293		91,531
Available for sale, Unrealized Losses - Twelve Months or Longer	(20,369)		(30,053)
Available for sale, Number of Holdings - Total	132		54
Available for sale, Fair Value - Total	1,432,146		497,151
Available for sale, Unrealized Losses - Total	(58,758)		(31,489)
Held-to-maturity, Fair Value - Less Than Twelve Months	1,155,980		185,788
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	(43,705)		(533)
Held-to-maturity, Fair Value - Twelve Months or Longer	2,166		2,858
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	(38)		(59)
Held-to-maturity, Number of Holdings - Total	99		24
Held-to-maturity, Fair Value - Total	1,158,146		188,646
Held-to-maturity, Unrealized Losses - Total	(43,743)		(592)
Total investment securities, Fair Value - Less Than Twelve Months	2,502,833		591,408
Total investment securities - Unrealized Losses - Less Than Twelve Months	82,094		1,969
Total investment securities - Fair Value - Twelve Months or Longer	87,459		94,389
Total investment securities, Unrealized Losses - Twelve Months or Longer	(20,407)		(30,112)
Total investment securities, Number of Holdings - Total	231		78
Total investment securities - Fair Value - Total	2,590,292		685,797
Total investment securities - Unrealized Losses - Total	(102,501)		(32,081)
Agency CMOs [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	128,352		69,936
Available for sale, Unrealized Losses - Less Than Twelve Months	(520)		(92)
Available for sale, Fair Value - Twelve Months or Longer	11,192		0
Available for sale, Unrealized Losses - Twelve Months or Longer	(207)
Available for sale, Number of Holdings - Total	8		4
Available for sale, Fair Value - Total	139,544		69,936
Available for sale, Unrealized Losses - Total	(727)		(92)
Held-to-maturity, Fair Value - Less Than Twelve Months	18,657		18,741
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	(801)		(8)
Held-to-maturity, Fair Value - Twelve Months or Longer	0
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	0
Held-to-maturity, Number of Holdings - Total	1		1
Held-to-maturity, Fair Value - Total	18,657		18,741
Held-to-maturity, Unrealized Losses - Total	(801)		(8)
Agency MBS [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	982,732		275,818
Available for sale, Unrealized Losses - Less Than Twelve Months	(36,261)		(1,098)
Available for sale, Fair Value - Twelve Months or Longer	3,065
Available for sale, Unrealized Losses - Twelve Months or Longer	(51)
Available for sale, Number of Holdings - Total	88		28
Available for sale, Fair Value - Total	985,797		275,818
Available for sale, Unrealized Losses - Total	(36,312)		(1,098)
Held-to-maturity, Fair Value - Less Than Twelve Months	1,035,839		161,057
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	(37,413)		(474)
Held-to-maturity, Fair Value - Twelve Months or Longer
Held-to-maturity, Unrealized Losses, Twelve Months or Longer
Held-to-maturity, Number of Holdings - Total	64		12
Held-to-maturity, Fair Value - Total	1,035,839		161,057
Held-to-maturity, Unrealized Losses - Total	(37,413)		(474)
CMBS [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	82,528		14,947
Available for sale, Unrealized Losses - Less Than Twelve Months	(897)		(17)
Available for sale, Fair Value - Twelve Months or Longer			20,909
Available for sale, Unrealized Losses - Twelve Months or Longer			(3,476)
Available for sale, Number of Holdings - Total	9		2
Available for sale, Fair Value - Total	82,528		35,856
Available for sale, Unrealized Losses - Total	(897)		(3,493)
Held-to-maturity, Fair Value - Less Than Twelve Months	83,221
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	(5,167)
Held-to-maturity, Fair Value - Twelve Months or Longer
Held-to-maturity, Unrealized Losses, Twelve Months or Longer
Held-to-maturity, Number of Holdings - Total	9
Held-to-maturity, Fair Value - Total	83,221
Held-to-maturity, Unrealized Losses - Total	(5,167)		0
CLOs [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	125,206		44,775
Available for sale, Unrealized Losses - Less Than Twelve Months	(474)		(225)
Available for sale, Fair Value - Twelve Months or Longer	0		0
Available for sale, Unrealized Losses - Twelve Months or Longer	0		0
Available for sale, Number of Holdings - Total	9		2
Available for sale, Fair Value - Total	125,206		44,775
Available for sale, Unrealized Losses - Total	(474)		(225)
Pooled trust preferred securities [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months			0
Available for sale, Unrealized Losses - Less Than Twelve Months
Available for sale, Fair Value - Twelve Months or Longer	30,215		26,207
Available for sale, Unrealized Losses - Twelve Months or Longer	(13,810)		(19,811)
Available for sale, Number of Holdings - Total	8		8
Available for sale, Fair Value - Total	30,215		26,207
Available for sale, Unrealized Losses - Total	(13,810)	[1]	(19,811)	[2]
Single issuer trust preferred securities [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	4,054		0
Available for sale, Unrealized Losses - Less Than Twelve Months	(91)
Available for sale, Fair Value - Twelve Months or Longer	40,821		44,415
Available for sale, Unrealized Losses - Twelve Months or Longer	(6,301)		(6,766)
Available for sale, Number of Holdings - Total	9		9
Available for sale, Fair Value - Total	44,875		44,415
Available for sale, Unrealized Losses - Total	(6,392)		(6,766)
Corporate debt [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months	23,981
Available for sale, Unrealized Losses - Less Than Twelve Months	(146)
Available for sale, Fair Value - Twelve Months or Longer
Available for sale, Unrealized Losses - Twelve Months or Longer
Available for sale, Number of Holdings - Total	1
Available for sale, Fair Value - Total	23,981
Available for sale, Unrealized Losses - Total	(146)		0	[3]
Equity securities - financial institutions [Member]
Schedule of Investments [Line Items]
Available for Sale, Fair Value - Less Than Twelve Months			144
Available for sale, Unrealized Losses - Less Than Twelve Months			(4)
Available for sale, Fair Value - Twelve Months or Longer
Available for sale, Unrealized Losses - Twelve Months or Longer
Available for sale, Number of Holdings - Total			1
Available for sale, Fair Value - Total			144
Available for sale, Unrealized Losses - Total	0	[4]	(4)	[3]
Municipal bonds and notes [Member]
Schedule of Investments [Line Items]
Held-to-maturity, Fair Value - Less Than Twelve Months	18,263		5,990
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	(324)		(51)
Held-to-maturity, Fair Value - Twelve Months or Longer	2,166		2,858
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	(38)		(59)
Held-to-maturity, Number of Holdings - Total	25		11
Held-to-maturity, Fair Value - Total	20,429		8,848
Held-to-maturity, Unrealized Losses - Total	$ (362)		$ (110)

[1] Amortized cost is net of $10.5 million of credit related other-than-temporary impairment at June 30, 2013.

[2] Amortized cost is net of $10.5 million of credit related other-than-temporary impairment at December 31, 2012.

[3] Amortized cost is net of $21.3 million of other-than-temporary impairment at December 31, 2012.

[4] Amortized cost is net of $21.3 million of other-than-temporary impairment at June 30, 2013.