Loans Receivable (excluding Covered Loans) - Changes in the Accretable Yield for Acquired Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Accretion, carrying amount of loans	$ 140	$ 802
Credit Impaired Acquired Loans [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period, accretable yield	32,591	37,236
Balance at beginning of period, carrying amount of loans	57,771	69,718
Reclassification from nonaccretable balance, net, accretable yield		7,300
Reclassification from nonaccretable balance, net, carrying value of loans		0
Accretion, accretable yield	(2,970)	(11,945)
Accretion, carrying amount of loans	2,970	11,945
Transfers to REO, accretable yield		0
Transfers to REO, carrying amount of loans		(1,188)
Payments received, net, accretable yield	0	0
Payments received, net, carrying amount of loans	(6,455)	(22,704)
Balance at end of period, accretable yield	29,621	32,591
Balance at end of period, carrying amount of loans	54,286	57,771
Acquired Non-Impaired Loans [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period, accretable yield	4,254	4,977
Balance at beginning of period, carrying amount of loans	177,440	245,373
Reclassification from nonaccretable balance, net, accretable yield		0
Reclassification from nonaccretable balance, net, carrying value of loans		0
Accretion, accretable yield	(1,424)	(723)
Accretion, carrying amount of loans	1,424	723
Transfers to REO, accretable yield		0
Transfers to REO, carrying amount of loans		(4,710)
Payments received, net, accretable yield	0	0
Payments received, net, carrying amount of loans	(1,193)	(63,946)
Balance at end of period, accretable yield	2,830	4,254
Balance at end of period, carrying amount of loans	$ 177,671	$ 177,440

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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- Definition

Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Certain Loans Acquired in Transfer not Accounted for as Debt Securities Accretable Yield, Payments

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Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Transfers to Real Estate Owned

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- Definition

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount of Loans, Reclassifications from Nonaccretable Difference

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Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Payments

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Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Transfers to Real Estate Owned

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- Definition

FDIC Indemnification Asset, Discount Accretion

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