Quality of Non-Covered Loans (Detail) (USD $)	Jun. 30, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Covered Loans	$ 31,966,411,000		$ 29,821,715,000
Multi-Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Covered Loans	22,310,512,000		20,699,927,000
Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non- Accrual	2,100,000
Non-Covered Loans	7,619,751,000		7,364,231,000
One-to-four family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Covered Loans	689,966,000		560,730,000
Acquisition, Development and Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non- Accrual	935,000
Non-Covered Loans	343,598,000		344,100,000
Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non- Accrual	499,000
Non-Covered Loans	966,888,000	[1],[2]	813,691,000	[2],[3]
Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-Covered Loans	35,696,000		39,036,000
Non-Covered Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	4,026,000		37,089,000
Non- Accrual	78,614,000		103,537,000
Total Past Due	82,640,000		140,626,000
Current	31,883,771,000		29,681,089,000
Non-Covered Loans | Multi-Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	1,082,000		33,678,000
Non- Accrual	33,668,000		58,395,000
Total Past Due	34,750,000		92,073,000
Current	22,275,762,000		20,607,854,000
Non-Covered Loans | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	878,000		1,854,000
Non- Accrual	27,054,000		24,550,000
Total Past Due	27,932,000		26,404,000
Current	7,591,819,000		7,337,827,000
Non-Covered Loans | One-to-four family
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	1,641,000		1,076,000
Non- Accrual	9,189,000		10,937,000
Total Past Due	10,830,000		12,013,000
Current	679,136,000		548,717,000
Non-Covered Loans | Acquisition, Development and Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0
Non- Accrual	2,328,000		2,571,000
Total Past Due	2,328,000		2,571,000
Current	341,270,000		341,529,000
Non-Covered Loans | Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	[1]	1,000	[3]
Non- Accrual	5,132,000	[1]	5,735,000	[3]
Total Past Due	5,132,000	[1]	5,736,000	[3]
Current	961,756,000	[1]	807,955,000	[3]
Non-Covered Loans | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	425,000		480,000
Non- Accrual	1,243,000		1,349,000
Total Past Due	1,668,000		1,829,000
Current	$ 34,028,000		$ 37,207,000

[1] Includes lease financing receivables, all of which were current at June 30, 2014.

[2] Includes lease financing receivables, all of which were classified as "pass."

[3] Includes lease financing receivables, all of which were current at December 31, 2013.