Loans (Analysis of Impaired Loans) (Details) (Loans, Excluding Purchased Credit Impaired Loans [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	$ 5,203,960		$ 5,186,695
Recorded Investment of Loans Individually Measured for Specific Impairment	27,096		28,099
Recorded Investment	25,893		26,883
Unpaid Principal Balance	31,634		38,433
Related Allowance	230		241
Average Recorded Investment Impaired Loans	27,596	26,538
Interest Recognized on Impaired Loans	267	336
Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	2,044,486		2,023,104
Recorded Investment of Loans Individually Measured for Specific Impairment	10,873		10,524
Recorded Investment	96		99
Unpaid Principal Balance	96		99
Related Allowance	24		25
Average Recorded Investment Impaired Loans	10,698	6,232
Interest Recognized on Impaired Loans	7	17
Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	79,219		80,091
Recorded Investment of Loans Individually Measured for Specific Impairment	0		2
Recorded Investment	0		2
Unpaid Principal Balance	0		2
Related Allowance	0		2
Average Recorded Investment Impaired Loans	1	31
Interest Recognized on Impaired Loans	0	0
One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	166,129		169,619
Recorded Investment of Loans Individually Measured for Specific Impairment	4,178		2,145
Recorded Investment	420		424
Unpaid Principal Balance	461		465
Related Allowance	115		120
Average Recorded Investment Impaired Loans	3,162	1,856
Interest Recognized on Impaired Loans	13	13
Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	192,972		189,779
Recorded Investment of Loans Individually Measured for Specific Impairment	470		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	235	111
Interest Recognized on Impaired Loans	0	0
Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	1,307,556		1,295,650
Recorded Investment of Loans Individually Measured for Specific Impairment	1,988		6,349
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	4,168	6,436
Interest Recognized on Impaired Loans	10	62
Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	839,157		835,895
Recorded Investment of Loans Individually Measured for Specific Impairment	7,030		8,846
Recorded Investment	578		582
Unpaid Principal Balance	578		582
Related Allowance	24		27
Average Recorded Investment Impaired Loans	7,938	10,140
Interest Recognized on Impaired Loans	234	241
Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	15,818		16,401
Recorded Investment of Loans Individually Measured for Specific Impairment	980		109
Recorded Investment	109		109
Unpaid Principal Balance	108		109
Related Allowance	67		67
Average Recorded Investment Impaired Loans	544	1,569
Interest Recognized on Impaired Loans	1	1
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	104,752		98,521
Recorded Investment of Loans Individually Measured for Specific Impairment	893		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	446	0
Interest Recognized on Impaired Loans	0	0
Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	62,958		73,783
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	55,439		58,944
Recorded Investment of Loans Individually Measured for Specific Impairment	0		0
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment of Loans Collectively Measured for Contingency Provision	335,474		344,908
Recorded Investment of Loans Individually Measured for Specific Impairment	684		124
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Related Allowance	0		0
Average Recorded Investment Impaired Loans	404	163
Interest Recognized on Impaired Loans	2	2
Impaired Loans With Recorded Allowance [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	1,203		1,216
Unpaid Principal Balance	1,243		1,257
Impaired Loans Without Recorded Allowance [Member] | Secured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	10,777		10,425
Unpaid Principal Balance	12,986		12,410
Impaired Loans Without Recorded Allowance [Member] | Unsecured Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | One-to-Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	3,758		1,721
Unpaid Principal Balance	4,220		2,370
Impaired Loans Without Recorded Allowance [Member] | Commercial Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	470		0
Unpaid Principal Balance	470		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	1,988		6,349
Unpaid Principal Balance	2,355		10,720
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	6,452		8,264
Unpaid Principal Balance	8,944		12,732
Impaired Loans Without Recorded Allowance [Member] | Land And Acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	871		0
Unpaid Principal Balance	871		0
Impaired Loans Without Recorded Allowance [Member] | Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	893		0
Unpaid Principal Balance	893		0
Impaired Loans Without Recorded Allowance [Member] | Income Property Multifamily Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | Owner Occupied Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	0		0
Unpaid Principal Balance	0		0
Impaired Loans Without Recorded Allowance [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment	684		124
Unpaid Principal Balance	$ 895		$ 201