Loans (Analysis of Impaired Loans) (Details) - Loans, Excluding Purchased Credit Impaired Loans [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	$ 5,387,823		$ 5,387,823		$ 5,186,695
Recorded Investment of Loans Individually Measured for Specific Impairment	21,707		21,707		28,099
Recorded Investment	19,379		19,379		26,883
Unpaid Principal Balance	24,795		24,795		38,433
Related Allowance	1,358		1,358		241
Average Recorded Investment Impaired Loans	24,401	$ 26,371	25,634	$ 26,377
Interest Recognized on Impaired Loans	280	341	545	677
Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	2,160,836		2,160,836		2,023,104
Recorded Investment of Loans Individually Measured for Specific Impairment	7,590		7,590		10,524
Recorded Investment	1,230		1,230		99
Unpaid Principal Balance	1,231		1,231		99
Related Allowance	1,161		1,161		25
Average Recorded Investment Impaired Loans	9,231	6,933	9,662	6,318
Interest Recognized on Impaired Loans	8	17	15	33
Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	82,224		82,224		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	23	1	27
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	174,430		174,430		169,619
Recorded Investment of Loans Individually Measured for Specific Impairment	4,183		4,183		2,145
Recorded Investment	416		416		424
Unpaid Principal Balance	458		458		465
Related Allowance	111		111		120
Average Recorded Investment Impaired Loans	4,180	2,069	3,502	1,920
Interest Recognized on Impaired Loans	11	11	24	23
Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	209,273		209,273		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	235	103	157	107
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	1,311,944		1,311,944		1,295,650
Recorded Investment of Loans Individually Measured for Specific Impairment	1,944		1,944		6,349
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment Impaired Loans	1,966	7,213	3,427	6,946
Interest Recognized on Impaired Loans	23	74	33	136
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	853,498		853,498		835,895
Recorded Investment of Loans Individually Measured for Specific Impairment	6,103		6,103		8,846
Recorded Investment	575		575		582
Unpaid Principal Balance	574		574		582
Related Allowance	20		20		27
Average Recorded Investment Impaired Loans	6,567	9,222	7,326	9,817
Interest Recognized on Impaired Loans	235	235	468	476
Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	15,849		15,849		16,401
Recorded Investment of Loans Individually Measured for Specific Impairment	968		968		109
Recorded Investment	107		107		109
Unpaid Principal Balance	107		107		109
Related Allowance	66		66		67
Average Recorded Investment Impaired Loans	974	653	686	1,083
Interest Recognized on Impaired Loans	2	1	3	3
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	108,219		108,219		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	595	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	64,557		64,557		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	63,022		63,022		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	343,971		343,971		344,908
Recorded Investment of Loans Individually Measured for Specific Impairment	26		26		124
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment Impaired Loans	355	155	278	159
Interest Recognized on Impaired Loans	1	$ 3	2	$ 5
Impaired Loans With Recorded Allowance [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	2,328		2,328		1,216
Unpaid Principal Balance	2,370		2,370		1,257
Impaired Loans Without Recorded Allowance [Member] | Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	6,360		6,360		10,425
Unpaid Principal Balance	8,169		8,169		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	3,767		3,767		1,721
Unpaid Principal Balance	4,428		4,428		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	1,944		1,944		6,349
Unpaid Principal Balance	2,326		2,326		10,720
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	5,528		5,528		8,264
Unpaid Principal Balance	8,008		8,008		12,732
Impaired Loans Without Recorded Allowance [Member] | Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	861		861		0
Unpaid Principal Balance	866		866		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	26		26		124
Unpaid Principal Balance	$ 105		$ 105		$ 201