Securities (Tables)

12 Months Ended

Dec. 31, 2011

Securities

Summary of amortized cost and estimated fair value for the major categories of securities available-for-sale and held-to-maturity

(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
December 31, 2011
Securities available-for-sale:
U.S. Treasury	$	19,163	$	24	$	(5	)	$	19,182
Federal agency—Debt		1,967,928		6,230		(296	)		1,973,862
Federal agency—MBS		650,091		31,040		(87	)		681,044
CMOs—Federal agency		4,239,205		89,926		(2,224	)		4,326,907
CMOs—Non-agency		79,999		322		(11,320	)		69,001
State and municipal		383,210		18,767		(373	)		401,604
Other debt securities		106,051		1,896		(8,873	)		99,074
Total debt securities		7,445,647		148,205		(23,178	)		7,570,674
Equity securities and mutual funds		352		875		—			1,227
Total securities available-for-sale	$	7,445,999	$	149,080	$	(23,178	)	$	7,571,901
Securities held-to-maturity (1):
Federal agency—Debt	$	40,423	$	780	$	—		$	41,203
Federal agency—MBS		75,231		1,632		—			76,863
CMOs—Federal agency		292,547		2,580		(195	)		294,932
State and municipal		59,479		1,463		(37	)		60,905
Total securities held-to-maturity	$	467,680	$	6,455	$	(232	)	$	473,903
December 31, 2010
Securities available-for-sale:
U.S. Treasury	$	14,070	$	47	$	(4	)	$	14,113
Federal agency—Debt		1,142,520		5,029		(5,221	)		1,142,328
Federal agency—MBS		540,768		13,379		(2,801	)		551,346
CMOs—Federal agency		3,442,238		65,494		(10,585	)		3,497,147
CMOs—Non-agency		126,819		1,147		(9,671	)		118,295
State and municipal		334,596		9,399		(615	)		343,380
Other debt securities		50,564		2,018		(8,952	)		43,630
Total debt securities		5,651,575		96,513		(37,849	)		5,710,239
Equity securities and mutual funds		6,545		3,891		—			10,436
Total securities available-for-sale	$	5,658,120	$	100,404	$	(37,849	)	$	5,720,675

        (1)   Securities held-to-maturity are presented in the consolidated balance sheets at amortized cost.

Schedule of gross realized gains and losses on sales and calls of securities available-for-sale

	For the year ended December 31,
(in thousands)	2011			2010			2009
Gross realized gains	$	6,747		$	6,915		$	22,696
Gross realized losses		(1,681	)		(6,522	)		(8,410	)
Net realized gains	$	5,066		$	393		$	14,286

Schedule of remaining maturities of debt securities included in the securities portfolio

(in thousands)	One year or less		Over 1 year through 5 years		Over 5 years through 10 years		Over 10 years		Total
Securities available-for-sale:
U.S. Treasury	$	15,037	$	4,145	$	—	$	—	$	19,182
Federal agency—Debt		1,509,730		464,132		—		—		1,973,862
Federal agency—MBS		18		288,795		275,369		116,862		681,044
CMOs—Federal agency		228,586		3,511,071		533,526		53,724		4,326,907
CMOs—Non-agency		11,322		32,416		25,263		—		69,001
State and municipal		48,082		202,844		99,581		51,097		401,604
Other		4,866		46,229		47,979		—		99,074
Total debt securities available-for-sale	$	1,817,641	$	4,549,632	$	981,718	$	221,683	$	7,570,674
Amortized cost	$	1,813,185	$	4,448,799	$	964,830	$	218,833	$	7,445,647
Securities held-to-maturity:
Federal agency—Debt	$	10,954	$	—	$	—	$	29,469	$	40,423
Federal agency—MBS		—		15,251		59,980		—		75,231
CMOs—Federal agency		—		214,600		32,651		45,296		292,547
State and municipal		—		2,532		53,429		3,518		59,479
Total debt securities held-to-maturity at amortized cost	$	10,954	$	232,383	$	146,060	$	78,283	$	467,680

Schedule of total impairment losses recognized in earnings on other-than-temporarily impaired securities

	For the year ended December 31,
(in thousands) Impairment Losses on Other-Than-Temporarily Impaired Securities
	2011		2010		2009
Non-agency CMOs	$	651	$	1,738	$	4,409
Collateralized debt obligation income notes		—		—		9,282
Perpetual preferred stock		—		293		1,124
Equity securities and mutual funds		—		—		1,630
Total	$	651	$	2,031	$	16,445

Schedule of roll forward of credit-related other-than-temporary impairment recognized in earnings for debt securities

	For the year ended December 31,
(in thousands)	2011		2010
Balance, beginning of period	$	19,445	$	17,707
Subsequent credit-related impairment		651		1,712
Initial credit-related impairment		—		26
Balance, end of period	$	20,096	$	19,445

Summary of the gross unrealized losses and fair value of investment securities that are not deemed to be other-than-temporarily impaired aggregated by investment category and length of time

	Less than 12 months				12 months or greater				Total
(in thousands)	Fair Value		Estimated Unrealized Loss		Fair Value		Estimated Unrealized Loss		Fair Value		Estimated Unrealized Loss
December 31, 2011
Securities available-for-sale:
U.S. Treasury	$	4,145	$	5	$	—	$	—	$	4,145	$	5
Federal agency—Debt		409,129		296		—		—		409,129		296
Federal agency—MBS		24,519		87		—		—		24,519		87
CMOs—Federal agency		744,737		2,224		—		—		744,737		2,224
CMOs—Non-agency		20,094		833		31,400		10,487		51,494		11,320
State and municipal		42,164		268		2,023		105		44,187		373
Other debt securities		34,153		508		14,718		8,365		48,871		8,873
Total securities available-for-sale	$	1,278,941	$	4,221	$	48,141	$	18,957	$	1,327,082	$	23,178
Securities held-to-maturity:
CMOs—Federal agency	$	32,256	$	195	$	—	$	—	$	32,256	$	195
State and municipal		5,784		37		—		—		5,784		37
Total securities held-to-maturity	$	38,040	$	232	$	—	$	—	$	38,040	$	232
December 31, 2010
Securities available-for-sale:
U.S. Treasury	$	5,028	$	4	$	—	$	—	$	5,028	$	4
Federal agency—Debt		561,205		5,221		—		—		561,205		5,221
Federal agency—MBS		109,381		2,801		—		—		109,381		2,801
CMOs—Federal agency		755,751		10,585		—		—		755,751		10,585
CMOs—Non-agency		7,718		18		61,571		9,653		69,289		9,671
State and municipal		25,845		558		700		57		26,545		615
Other debt securities		—		—		14,407		8,952		14,407		8,952
Total securities available-for-sale	$	1,464,928	$	19,187	$	76,678	$	18,662	$	1,541,606	$	37,849