Loans Receivable and Allowance for Loan Losses (Details 5) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Recorded Investment
Total	$ 12,009,959	$ 12,386,378
Past due 90 days or more	38,170	250,534
Consumer and Other Loans
Recorded Investment
Total	239,229	239,681
Past due 90 days or more	5,685	5,948
Consumer and Other Loans | Home equity lines of credit
Recorded Investment
Total	188,821	199,809
Past due 90 days or more	5,648	5,916
Consumer and Other Loans | Other Loans
Recorded Investment
Total	50,408	39,872
Past due 90 days or more	37	32
Mortgage Loans (Gross)
Recorded Investment
Total	11,770,730	12,146,697
Past due 90 days or more	32,485	244,586
Mortgage Loans (Gross) | Residential Mortgage Loans
Recorded Investment
Total	7,324,674	8,037,276
Past due 90 days or more	21,723	234,378
Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Interest-only Loans
Recorded Investment
Total	1,092,216	1,382,201
Past due 90 days or more	5,565	78,271
Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Amortizing Loans
Recorded Investment
Total	5,162,689	5,419,457
Past due 90 days or more	6,542	42,085
Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Interest-only Loans
Recorded Investment
Total	684,578	839,661
Past due 90 days or more	8,066	87,910
Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Amortizing Loans
Recorded Investment
Total	385,191	395,957
Past due 90 days or more	1,550	26,112
Performing | Consumer and Other Loans | Home equity lines of credit
Recorded Investment
Total	183,094	193,861
Performing | Consumer and Other Loans | Other Loans
Recorded Investment
Total	50,371	39,840
Performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Interest-only Loans
Recorded Investment
Total	1,064,667	1,281,973
Performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Amortizing Loans
Recorded Investment
Total	5,149,312	5,364,548
Performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Interest-only Loans
Recorded Investment
Total	648,036	721,503
Performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Amortizing Loans
Recorded Investment
Total	379,948	363,626
Non-performing | Consumer and Other Loans | Home equity lines of credit
Recorded Investment
Current or past due less than 90 days	79	32
Past due 90 days or more	5,648	5,916
Non-performing | Consumer and Other Loans | Other Loans
Recorded Investment
Past due 90 days or more	37	32
Non-performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Interest-only Loans
Recorded Investment
Current or past due less than 90 days	21,984	21,957
Past due 90 days or more	5,565	78,271
Non-performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Full Documentation Amortizing Loans
Recorded Investment
Current or past due less than 90 days	6,835	12,824
Past due 90 days or more	6,542	42,085
Non-performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Interest-only Loans
Recorded Investment
Current or past due less than 90 days	28,476	30,248
Past due 90 days or more	8,066	87,910
Non-performing | Mortgage Loans (Gross) | Residential Mortgage Loans | Reduced Documentation Amortizing Loans
Recorded Investment
Current or past due less than 90 days	3,693	6,219
Past due 90 days or more	$ 1,550	$ 26,112