Loans (Analysis of Impaired Loans) (Details) - Loans, Excluding Purchased Credit Impaired Loans [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	$ 5,536,565		$ 5,536,565		$ 5,186,695
Recorded Investment of Loans Individually Measured for Specific Impairment	18,880		18,880		28,099
Recorded Investment	16,470		16,470		26,883
Unpaid Principal Balance	21,257		21,257		38,433
Related Allowance	1,199		1,199		241
Average Recorded Investment Impaired Loans	20,293	$ 26,000	23,946	$ 26,269
Interest Recognized on Impaired Loans	91	342	612	1,019
Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	2,260,544		2,260,544		2,023,104
Recorded Investment of Loans Individually Measured for Specific Impairment	5,424		5,424		10,524
Recorded Investment	1,402		1,402		99
Unpaid Principal Balance	1,412		1,412		99
Related Allowance	1,020		1,020		25
Average Recorded Investment Impaired Loans	6,507	6,869	8,602	6,550
Interest Recognized on Impaired Loans	3	17	10	50
Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	83,739		83,739		80,091
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0		2
Recorded Investment	0		0		2
Unpaid Principal Balance	0		0		2
Related Allowance	0		0		2
Average Recorded Investment Impaired Loans	0	15	1	23
Interest Recognized on Impaired Loans	0	0	0	1
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	171,669		171,669		169,619
Recorded Investment of Loans Individually Measured for Specific Impairment	2,448		2,448		2,145
Recorded Investment	317		317		424
Unpaid Principal Balance	341		341		465
Related Allowance	84		84		120
Average Recorded Investment Impaired Loans	3,315	2,307	3,238	2,082
Interest Recognized on Impaired Loans	11	14	35	37
Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	208,412		208,412		189,779
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0		0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment Impaired Loans	0	94	118	102
Interest Recognized on Impaired Loans	0	0	0	0
Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	1,320,287		1,320,287		1,295,650
Recorded Investment of Loans Individually Measured for Specific Impairment	2,177		2,177		6,349
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment Impaired Loans	2,061	7,345	3,114	6,891
Interest Recognized on Impaired Loans	10	69	27	205
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	889,085		889,085		835,895
Recorded Investment of Loans Individually Measured for Specific Impairment	7,229		7,229		8,846
Recorded Investment	571		571		582
Unpaid Principal Balance	571		571		582
Related Allowance	17		17		27
Average Recorded Investment Impaired Loans	6,665	9,117	7,302	9,629
Interest Recognized on Impaired Loans	65	239	533	715
Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	13,854		13,854		16,401
Recorded Investment of Loans Individually Measured for Specific Impairment	681		681		109
Recorded Investment	106		106		109
Unpaid Principal Balance	106		106		109
Related Allowance	64		64		67
Average Recorded Investment Impaired Loans	825	111	685	840
Interest Recognized on Impaired Loans	1	1	4	4
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	120,414		120,414		98,521
Recorded Investment of Loans Individually Measured for Specific Impairment	893		893		0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment Impaired Loans	893	0	670	0
Interest Recognized on Impaired Loans	0	0	0	0
Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	63,182		63,182		73,783
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0		0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	69,243		69,243		58,944
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0		0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	336,136		336,136		344,908
Recorded Investment of Loans Individually Measured for Specific Impairment	28		28		124
Recorded Investment	14		14		0
Unpaid Principal Balance	15		15		0
Related Allowance	14		14		0
Average Recorded Investment Impaired Loans	27	142	216	152
Interest Recognized on Impaired Loans	1	$ 2	3	$ 7
Impaired Loans With Recorded Allowance [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	2,410		2,410		1,216
Unpaid Principal Balance	2,445		2,445		1,257
Impaired Loans Without Recorded Allowance [Member] | Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	4,022		4,022		10,425
Unpaid Principal Balance	5,312		5,312		12,410
Impaired Loans Without Recorded Allowance [Member] | Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Impaired Loans Without Recorded Allowance [Member] | One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	2,131		2,131		1,721
Unpaid Principal Balance	2,903		2,903		2,370
Impaired Loans Without Recorded Allowance [Member] | Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	2,177		2,177		6,349
Unpaid Principal Balance	2,336		2,336		10,720
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	6,658		6,658		8,264
Unpaid Principal Balance	9,137		9,137		12,732
Impaired Loans Without Recorded Allowance [Member] | Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	575		575		0
Unpaid Principal Balance	591		591		0
Impaired Loans Without Recorded Allowance [Member] | Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	893		893		0
Unpaid Principal Balance	893		893		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Impaired Loans Without Recorded Allowance [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	14		14		124
Unpaid Principal Balance	$ 85		$ 85		$ 201