Allowance for Losses on Loans (Internally Assigned Grade) (Details) (USD $)	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2011 Pass [Member]	Sep. 30, 2011 Pass [Member]	Dec. 31, 2011 Special Mention [Member]	Sep. 30, 2011 Special Mention [Member]	Dec. 31, 2011 Substandard [Member]	Sep. 30, 2011 Substandard [Member]	Dec. 31, 2011 Doubtful [Member]	Sep. 30, 2011 Doubtful [Member]	Dec. 31, 2011 Loss [Member]	Sep. 30, 2011 Loss [Member]	Dec. 31, 2011 Nonperforming Financing Receivable [Member]	Jun. 30, 2010 Nonperforming Financing Receivable [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member] Pass [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member] Pass [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member] Special Mention [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member] Special Mention [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member] Substandard [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member] Substandard [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member] Doubtful [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member] Doubtful [Member]	Dec. 31, 2011 Residential Portfolio Segment [Member] Loss [Member]	Sep. 30, 2011 Residential Portfolio Segment [Member] Loss [Member]	Dec. 31, 2011 Construction, Speculative [Member]	Sep. 30, 2011 Construction, Speculative [Member]	Dec. 31, 2011 Construction, Speculative [Member] Pass [Member]	Sep. 30, 2011 Construction, Speculative [Member] Pass [Member]	Dec. 31, 2011 Construction, Speculative [Member] Special Mention [Member]	Sep. 30, 2011 Construction, Speculative [Member] Special Mention [Member]	Dec. 31, 2011 Construction, Speculative [Member] Substandard [Member]	Sep. 30, 2011 Construction, Speculative [Member] Substandard [Member]	Dec. 31, 2011 Construction, Speculative [Member] Doubtful [Member]	Sep. 30, 2011 Construction, Speculative [Member] Doubtful [Member]	Dec. 31, 2011 Construction, Speculative [Member] Loss [Member]	Sep. 30, 2011 Construction, Speculative [Member] Loss [Member]	Dec. 31, 2011 Construction, Custom [Member]	Sep. 30, 2011 Construction, Custom [Member]	Dec. 31, 2011 Construction, Custom [Member] Pass [Member]	Sep. 30, 2011 Construction, Custom [Member] Pass [Member]	Dec. 31, 2011 Construction, Custom [Member] Special Mention [Member]	Sep. 30, 2011 Construction, Custom [Member] Special Mention [Member]	Dec. 31, 2011 Construction, Custom [Member] Substandard [Member]	Sep. 30, 2011 Construction, Custom [Member] Substandard [Member]	Dec. 31, 2011 Construction, Custom [Member] Doubtful [Member]	Sep. 30, 2011 Construction, Custom [Member] Doubtful [Member]	Dec. 31, 2011 Construction, Custom [Member] Loss [Member]	Sep. 30, 2011 Construction, Custom [Member] Loss [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member] Pass [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member] Pass [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member] Special Mention [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member] Special Mention [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member] Substandard [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member] Substandard [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member] Doubtful [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member] Doubtful [Member]	Dec. 31, 2011 Land, Acquisition and Development [Member] Loss [Member]	Sep. 30, 2011 Land, Acquisition and Development [Member] Loss [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member] Pass [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member] Pass [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member] Special Mention [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member] Special Mention [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member] Substandard [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member] Substandard [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member] Doubtful [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member] Doubtful [Member]	Dec. 31, 2011 Land, Consumer Lot Loans [Member] Loss [Member]	Sep. 30, 2011 Land, Consumer Lot Loans [Member] Loss [Member]	Dec. 31, 2011 Multi Family Housing [Member]	Sep. 30, 2011 Multi Family Housing [Member]	Dec. 31, 2011 Multi Family Housing [Member] Pass [Member]	Sep. 30, 2011 Multi Family Housing [Member] Pass [Member]	Dec. 31, 2011 Multi Family Housing [Member] Special Mention [Member]	Sep. 30, 2011 Multi Family Housing [Member] Special Mention [Member]	Dec. 31, 2011 Multi Family Housing [Member] Substandard [Member]	Sep. 30, 2011 Multi Family Housing [Member] Substandard [Member]	Dec. 31, 2011 Multi Family Housing [Member] Doubtful [Member]	Sep. 30, 2011 Multi Family Housing [Member] Doubtful [Member]	Dec. 31, 2011 Multi Family Housing [Member] Loss [Member]	Sep. 30, 2011 Multi Family Housing [Member] Loss [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member] Pass [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member] Pass [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member] Special Mention [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member] Special Mention [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member] Substandard [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member] Substandard [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member] Doubtful [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member] Doubtful [Member]	Dec. 31, 2011 Commercial Real Estate Portfolio Segment [Member] Loss [Member]	Sep. 30, 2011 Commercial Real Estate Portfolio Segment [Member] Loss [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member] Pass [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member] Pass [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member] Special Mention [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member] Special Mention [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member] Substandard [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member] Substandard [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member] Doubtful [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member] Doubtful [Member]	Dec. 31, 2011 Commercial and Industrial Loans [Member] Loss [Member]	Sep. 30, 2011 Commercial and Industrial Loans [Member] Loss [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member] Pass [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member] Pass [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member] Special Mention [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member] Special Mention [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member] Substandard [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member] Substandard [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member] Doubtful [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member] Doubtful [Member]	Dec. 31, 2011 Home Equity Line of Credit [Member] Loss [Member]	Sep. 30, 2011 Home Equity Line of Credit [Member] Loss [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member] Pass [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member] Pass [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member] Special Mention [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member] Special Mention [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member] Substandard [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member] Substandard [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member] Doubtful [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member] Doubtful [Member]	Dec. 31, 2011 Consumer Portfolio Segment [Member] Loss [Member]	Sep. 30, 2011 Consumer Portfolio Segment [Member] Loss [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable, gross	$ 8,208,343,000	$ 8,299,074,000	$ 7,753,948,000	$ 7,804,613,000	$ 47,293,000	$ 76,285,000	$ 406,721,000	$ 415,550,000	$ 0	$ 2,245,000	$ 381,000	$ 381,000	$ 343,665,000	$ 442,699,000	$ 6,082,490,000	$ 6,218,878,000	$ 5,906,370,000	$ 6,047,279,000	$ 0	$ 0	$ 176,120,000	$ 171,599,000	$ 0	$ 0	$ 0	$ 0	$ 130,120,000	$ 140,459,000	$ 65,880,000	$ 56,485,000	$ 7,663,000	$ 21,035,000	$ 56,577,000	$ 62,939,000	$ 0	$ 0	$ 0	$ 0	$ 271,227,000	$ 279,851,000	$ 271,227,000	$ 279,851,000	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 175,965,000	$ 200,692,000	$ 41,528,000	$ 44,888,000	$ 24,028,000	$ 44,840,000	$ 110,409,000	$ 110,964,000	$ 0	$ 0	$ 0	$ 0	$ 154,874,000	$ 163,146,000	$ 154,228,000	$ 162,670,000	$ 261,000	$ 0	$ 385,000	$ 476,000	$ 0	$ 0	$ 0	$ 0	$ 689,149,000	$ 700,673,000	$ 653,006,000	$ 663,582,000	$ 6,193,000	$ 4,629,000	$ 29,950,000	$ 32,462,000	$ 0	$ 0	$ 0	$ 0	$ 415,394,000	$ 303,442,000	$ 377,668,000	$ 264,083,000	$ 7,276,000	$ 4,125,000	$ 30,450,000	$ 35,234,000	$ 0	$ 0	$ 0	$ 0	$ 93,792,000	$ 109,332,000	$ 89,705,000	$ 104,171,000	$ 1,344,000	$ 1,128,000	$ 2,362,000	$ 1,407,000	$ 0	$ 2,245,000	$ 381,000	$ 381,000	$ 132,089,000	$ 115,092,000	$ 132,089,000	$ 115,092,000	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 63,243,000	$ 67,509,000	$ 62,247,000	$ 66,512,000	$ 528,000	$ 528,000	$ 468,000	$ 469,000	$ 0	$ 0	$ 0	$ 0
Grade as percentage of total gross loans			94.50%	94.10%	0.60%	0.90%	4.90%	5.00%	0.00%	0.00%	0.00%	0.00%	2.52%	3.30%