Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 315,090	[1]	$ 429,266	[2]
Mortgage servicing rights	215,055		144,713
Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	105,889		177,255
Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	209,201		252,011
GSE certificates | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	29,389	[3]	92,679
GSE CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	63,130	[4]	67,160
Private label CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	13,370		17,416
Municipal bonds | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,180		46,296
Capital trust notes | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	34,659		38,435
Preferred stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	121,713		125,018
Common stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	51,649		42,262
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights	96		193
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	315,090		429,266
Loans held for sale	756,601		1,204,370
Mortgage servicing rights	214,959		144,520
Derivative assets-other	16,068	[5]	4,119	[5],[6]
Interest rate lock commitments	(6,653)
Derivative liabilities	(281)		(3,381)
Interest rate lock commitments			21,446
Fair Value, Measurements, Recurring | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	105,889		177,255
Fair Value, Measurements, Recurring | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	209,201		252,011
Fair Value, Measurements, Recurring | GSE certificates | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	29,389		92,679
Fair Value, Measurements, Recurring | GSE CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	63,130		67,160
Fair Value, Measurements, Recurring | Private label CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	13,370		17,416
Fair Value, Measurements, Recurring | Municipal bonds | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,180		46,296
Fair Value, Measurements, Recurring | Capital trust notes | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	34,659		38,435
Fair Value, Measurements, Recurring | Preferred stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	121,713		125,018
Fair Value, Measurements, Recurring | Common stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	51,649		42,262
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	143,223		164,416
Derivative assets-other	1,475	[5]	5,939	[5],[6]
Derivative liabilities	(767)		(2,303)
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	143,223		164,416
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Preferred stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	94,133		124,734
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Common stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	49,090		39,682
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	151,974		246,281
Loans held for sale	756,601		1,204,370
Derivative assets-other	50,581	[5]	2,910	[5],[6]
Derivative liabilities	(25,324)		(5,808)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	105,889		177,255
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	46,085		69,026
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | GSE certificates | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	29,389		92,679
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | GSE CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	63,130		67,160
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Private label CMOs | Mortgage-Related Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	13,370		17,416
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal bonds | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,180		46,296
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Capital trust notes | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	14,766		19,866
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Preferred stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	27,580		284
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Common stock | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	2,559		2,580
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	19,893		18,569
Mortgage servicing rights	214,959		144,520
Interest rate lock commitments	(6,653)
Interest rate lock commitments			21,446
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	19,893		18,569
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Capital trust notes | Other Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	19,893		18,569
Fair Value, Measurements, Recurring | Netting
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets-other	(35,988)	[5],[7]	(4,730)	[5],[6]
Derivative liabilities	$ 25,810	[7]	$ 4,730

[1] At June 30, 2013, the non-credit portion of OTTI recorded in accumulated other comprehensive loss ("AOCL") was $570,000 (before taxes).

[2] At December 31, 2012, the non-credit portion of OTTI recorded in AOCL was $570,000 (before taxes).

[3] Government-sponsored enterprises

[4] Collateralized mortgage obligations

[5] Includes $1.3 million to purchase Treasury options.

[6] Includes $5.3 million to purchase Treasury options.

[7] Includes cash collateral received and pledged.