Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 83,369	$ 75,646
Charged-offs	(2,988)	(4,307)
Recoveries	1,531	2,636
Provision for loan and lease losses	1,362	5,852
Ending balance	83,274	79,827
Specific Reserve	2,911	5,857
General Allocation	80,363	73,970
Secured Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	43,188	29,341
Charged-offs	(1,249)	(2,414)
Recoveries	323	553
Provision for loan and lease losses	1,355	9,851
Ending balance	43,617	37,331
Specific Reserve	2,829	5,657
General Allocation	40,788	31,674
Unsecured Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,626	2,000
Charged-offs	0	(63)
Recoveries	157	249
Provision for loan and lease losses	(288)	409
Ending balance	2,495	2,595
Specific Reserve	0	2
General Allocation	2,495	2,593
One-to-Four Family Residential [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	593	701
Charged-offs	(2)	0
Recoveries	17	172
Provision for loan and lease losses	8	(315)
Ending balance	616	558
Specific Reserve	8	22
General Allocation	608	536
Commercial Land [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,947	4,265
Charged-offs	0	0
Recoveries	7	6
Provision for loan and lease losses	634	(526)
Ending balance	4,588	3,745
Specific Reserve	0	0
General Allocation	4,588	3,745
Income Property Multifamily [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,044	5,672
Charged-offs	0	(223)
Recoveries	23	141
Provision for loan and lease losses	951	(888)
Ending balance	5,018	4,702
Specific Reserve	0	0
General Allocation	5,018	4,702
Owner Occupied [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,533	5,459
Charged-offs	0	0
Recoveries	1	12
Provision for loan and lease losses	432	(722)
Ending balance	4,966	4,749
Specific Reserve	52	5
General Allocation	4,914	4,744
Land And Acquisition [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	549	963
Charged-offs	0	0
Recoveries	59	16
Provision for loan and lease losses	(201)	(67)
Ending balance	407	912
Specific Reserve	0	0
General Allocation	407	912
Residential Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,536	3,709
Charged-offs	(170)	0
Recoveries	1	3
Provision for loan and lease losses	99	924
Ending balance	5,466	4,636
Specific Reserve	0	0
General Allocation	5,466	4,636
Income Property Multifamily Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,784	7,053
Charged-offs	0	0
Recoveries	0	0
Provision for loan and lease losses	(1,267)	421
Ending balance	4,517	7,474
Specific Reserve	0	0
General Allocation	4,517	7,474
Owner Occupied Construction [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,604	4,413
Charged-offs	0	0
Recoveries	0	0
Provision for loan and lease losses	(384)	(2,490)
Ending balance	2,220	1,923
Specific Reserve	0	0
General Allocation	2,220	1,923
Consumer Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,301	5,163
Charged-offs	(478)	(264)
Recoveries	238	260
Provision for loan and lease losses	484	57
Ending balance	5,545	5,216
Specific Reserve	22	171
General Allocation	5,523	5,045
Purchased Credit Impaired Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,611	6,907
Charged-offs	(1,089)	(1,343)
Recoveries	705	1,224
Provision for loan and lease losses	18	(1,123)
Ending balance	3,245	5,665
Specific Reserve	0	0
General Allocation	3,245	5,665
Unallocated Financing Receivables [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,053	0
Charged-offs	0	0
Recoveries	0	0
Provision for loan and lease losses	(479)	321
Ending balance	574	321
Specific Reserve	0	0
General Allocation	$ 574	$ 321