Available For Sale Securities Pledged As Collateral Amortized Cost

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- Definition

Amount of equity interest in a Federal Home Loan Bank (FHLB), acquired at the acquisition date.

+ References

No definition available.

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- Definition

Federal Home Loan Bank Minimum Stock Ownership As Percent Of Outstanding Advances

+ References

No definition available.

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- Definition

Purchases of FHLB Stock

+ References

No definition available.

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- Definition

Redemptions of FHLB stock during the period

+ References

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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- Definition

Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

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- Definition

The change during the period, either increase or decrease, in total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(b))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Investment Securities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 20, 2017	Oct. 06, 2015
Schedule of Available-for-sale Securities [Line Items]
Available For Sale Securities Pledged As Collateral Amortized Cost	$ 449,200
Proceeds from sales of securities available-for-sale	759,300	$ 393,509	$ 1,035,926
Available-for-sale Securities, Gross Realized Gains	3,300	11,100	4,500
Available-for-sale Securities, Gross Realized Losses	3,800	1,600	700
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax	24,709	(16,244)	3,621
Federal Home Loan Bank stock, at cost	$ 20,790	$ 21,870
Federal Home Loan Bank Minimum Stock Ownership As Percent Of Outstanding Advances	0.00%	2.70%
Purchases of FHLB Stock	$ 12,800
Redemptions of FHLB stock	(25,800)
Federal Home Loan Bank of San Francisco [Member]
Schedule of Available-for-sale Securities [Line Items]
Increase (Decrease) in Marketable Securities, Restricted	(1,100)
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available-for-sale	355,400	$ 384,000	208,400
CU Bancorp [Member]
Schedule of Available-for-sale Securities [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities				$ 446,980
FHLB stock				$ 11,902
Square 1 Financial, Inc. [Member]
Schedule of Available-for-sale Securities [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities					$ 2,193,538
FHLB stock					$ 2,787
CU Bancorp [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	0
CU Bancorp [Member] \| Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available-for-sale	$ 404,500
Square 1 Financial, Inc. [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains			0
Square 1 Financial, Inc. [Member] \| Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available-for-sale			$ 823,800