Loans Receivable and Allowance for Loan Losses (Details 4) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Nonaccrual and Past Due Loans
Total Loans	$ 2,629,754	$ 2,585,329	$ 2,350,250
Originated
Nonaccrual and Past Due Loans
30-59 Days Past Due	264	500
60-89 Days Past Due	62	30
90 Days or More Past Due (includes nonaccrual)	1,300	1,407
Total Past Due	1,626	1,937
Current	2,494,692	2,430,851
Total Loans	2,496,318	2,432,788
Nonaccrual Loans	1,300	1,407
Acquired
Nonaccrual and Past Due Loans
30-59 Days Past Due	1,028	24
90 Days or More Past Due (includes nonaccrual)	572	1,954
Total Past Due	1,600	1,978
Current	131,836	150,563
Total Loans	133,436	152,541
Nonaccrual Loans	572	1,954
Commercial and industrial
Nonaccrual and Past Due Loans
Total Loans	323,890	353,921	291,208
Commercial and industrial \| Originated
Nonaccrual and Past Due Loans
30-59 Days Past Due		88
60-89 Days Past Due	15	30
90 Days or More Past Due (includes nonaccrual)	976	938
Total Past Due	991	1,056
Current	301,880	327,655
Total Loans	302,871	328,711
Nonaccrual Loans	976	938
Commercial and industrial \| Acquired
Nonaccrual and Past Due Loans
90 Days or More Past Due (includes nonaccrual)	572	576
Total Past Due	572	576
Current	20,447	24,634
Total Loans	21,019	25,210
Nonaccrual Loans	572	576
Owner occupied \| Originated
Nonaccrual and Past Due Loans
Current	295,416	304,303
Total Loans	295,416	304,303
Owner occupied \| Acquired
Nonaccrual and Past Due Loans
Current	44,241	49,173
Total Loans	44,241	49,173
Non-owner occupied \| Originated
Nonaccrual and Past Due Loans
90 Days or More Past Due (includes nonaccrual)	273	289
Total Past Due	273	289
Current	876,003	849,501
Total Loans	876,276	849,790
Nonaccrual Loans	273	289
Non-owner occupied \| Acquired
Nonaccrual and Past Due Loans
30-59 Days Past Due	1,028
90 Days or More Past Due (includes nonaccrual)		1,072
Total Past Due	1,028	1,072
Current	51,706	53,516
Total Loans	52,734	54,588
Nonaccrual Loans		1,072
Residential \| Originated
Nonaccrual and Past Due Loans
Current	172,391	158,915
Total Loans	172,391	158,915
Residential \| Acquired
Nonaccrual and Past Due Loans
Current	3,292	6,156
Total Loans	3,292	6,156
Commercial \| Originated
Nonaccrual and Past Due Loans
Current	314,265	265,830
Total Loans	314,265	265,830
Commercial \| Acquired
Nonaccrual and Past Due Loans
Current	837	4,007
Total Loans	837	4,007
Single family \| Originated
Nonaccrual and Past Due Loans
30-59 Days Past Due	15	359
Total Past Due	15	359
Current	293,696	297,530
Total Loans	293,711	297,889
Single family \| Acquired
Nonaccrual and Past Due Loans
30-59 Days Past Due		24
90 Days or More Past Due (includes nonaccrual)		306
Total Past Due		330
Current	7,129	8,454
Total Loans	7,129	8,784
Nonaccrual Loans		306
Multi-family \| Originated
Nonaccrual and Past Due Loans
Current	105,527	96,005
Total Loans	105,527	96,005
Home Equity Lines
Nonaccrual and Past Due Loans
Total Loans	135,276	130,885	115,045
Home Equity Lines \| Originated
Nonaccrual and Past Due Loans
30-59 Days Past Due	243
90 Days or More Past Due (includes nonaccrual)	51	180
Total Past Due	294	180
Current	131,502	126,824
Total Loans	131,796	127,004
Nonaccrual Loans	51	180
Home Equity Lines \| Acquired
Nonaccrual and Past Due Loans
Current	3,480	3,881
Total Loans	3,480	3,881
Installment \| Originated
Nonaccrual and Past Due Loans
Current	3,760	3,920
Total Loans	3,760	3,920
Installment \| Acquired
Nonaccrual and Past Due Loans
Current	704	742
Total Loans	704	742
Credit cards \| Originated
Nonaccrual and Past Due Loans
30-59 Days Past Due	6	53
60-89 Days Past Due	47
Total Past Due	53	53
Current	252	368
Total Loans	$ 305	$ 421

Financing receivables that are less than 60 days past due but more than 29 days past due.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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Financing receivables that are current.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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