Loans Receivable and Allowance for Loan Losses (Average Recorded Investment, Interest Income Recognized and Cash Basis Interest Income on Impaired Loans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment	$ 314,118	$ 389,861	$ 350,631	$ 399,587
Interest income recognized	2,450	2,912	8,303	8,617
Cash basis interest income	2,482	3,091	8,472	9,121
Consumer and other loans | Home equity lines of credit
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	5,546		5,215
Interest income recognized, loans with an allowance recorded	5		37
Cash basis interest income, loans with an allowance recorded	13		51
Mortgage loans | Residential | Full documentation interest-only
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	78,799	107,893	93,748	105,931
Average recorded investment, loans without an allowance recorded		9,075		14,433
Interest income recognized, loans with an allowance recorded	440	762	1,644	2,114
Cash basis interest income, loans with an allowance recorded	461	763	1,695	2,229
Mortgage loans | Residential | Full documentation amortizing loans
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	38,051	31,128	37,926	29,465
Average recorded investment, loans without an allowance recorded	314	2,968	457	4,396
Interest income recognized, loans with an allowance recorded	289	218	993	623
Cash basis interest income, loans with an allowance recorded	283	220	992	639
Mortgage loans | Residential | Reduced documentation interest-only
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	104,522	144,468	120,976	146,773
Average recorded investment, loans without an allowance recorded				2,086
Interest income recognized, loans with an allowance recorded	782	1,171	2,922	3,053
Cash basis interest income, loans with an allowance recorded	814	1,174	2,939	3,205
Mortgage loans | Residential | Reduced documentation amortizing
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	20,781	24,452	23,142	25,424
Interest income recognized, loans with an allowance recorded	141	158	478	464
Cash basis interest income, loans with an allowance recorded	147	152	482	493
Mortgage loans | Multi-family
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	33,013	19,557	30,836	18,975
Average recorded investment, loans without an allowance recorded	13,419	31,464	17,906	33,294
Interest income recognized, loans with an allowance recorded	329	34	952	659
Interest income recognized, loans without an allowance recorded	175	401	529	1,165
Cash basis interest income, loans with an allowance recorded	328	169	970	722
Cash basis interest income, loans without an allowance recorded	175	416	530	1,229
Mortgage loans | Commercial real estate
Average recorded investment, interest income recognized and cash basis interest income related to impaired mortgage loans by segment and class
Average recorded investment, loans with an allowance recorded	19,673	7,604	16,859	8,692
Average recorded investment, loans without an allowance recorded		11,252	3,566	10,118
Interest income recognized, loans with an allowance recorded	289	56	748	253
Interest income recognized, loans without an allowance recorded		112		286
Cash basis interest income, loans with an allowance recorded	261	66	813	285
Cash basis interest income, loans without an allowance recorded		$ 131		$ 319