Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) Modifications contract	Sep. 30, 2017 USD ($) Modifications contract	Sep. 30, 2018 USD ($) Modifications contract	Sep. 30, 2017 USD ($) Modifications contract	Dec. 31, 2017 USD ($)
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0	0	0
Loans and Leases Receivable, Related Parties	$ 9,700		$ 9,700		$ 10,000
Financing Receivable Modifications Additional Commitment To Lend	$ 16,200		$ 16,200		$ 506
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	4	24	28	48
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 14,634	$ 7,961	$ 21,036	$ 12,482
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 14,634	$ 7,961	$ 21,036	$ 12,482
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Secured Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	2	9	7
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 14,511	$ 808	$ 17,605	$ 2,586
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 14,511	$ 808	$ 17,605	$ 2,586
Loans, Excluding Purchased Credit Impaired Loans [Member] \| One-to-Four Family Residential [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	2	0	3
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0	$ 201	$ 0	$ 583
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 201	$ 0	$ 583
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Income Property Multifamily [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	1	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0	$ 1,152	$ 891	$ 1,152
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 1,152	$ 891	$ 1,152
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	0	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0	$ 78	$ 0	$ 78
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 78	$ 0	$ 78
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Owner Occupied Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	0	1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0	$ 4,050	$ 0	$ 4,050
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0	$ 4,050	$ 0	$ 4,050
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	3	17	18	35
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 123	$ 1,672	$ 2,540	$ 4,033
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 123	$ 1,672	$ 2,540	$ 4,033

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Number of financing receivables that have been modified by troubled debt restructurings.

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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