Debt Collateral, Number of Affiliate Banks

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- Definition

Debt Collateral, Number of Required Investment Accounts

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

+ Details

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

No definition available.

+ Details

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- Definition

The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
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- Definition

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Cash and Investments (Narrative) (Details)	3 Months Ended	6 Months Ended
Cash and Investments (Narrative) (Details)	Jun. 30, 2017 USD ($) investment	Jun. 30, 2017 USD ($) account investment affiliate	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Investment [Line Items]
Number of required investment accounts \| account		1
Number of affiliate banks \| affiliate		1
Gain (loss) on sale of available-for-sale securities	$ 0	$ 0
Other-than-temporary impairment charges on available-for-sale securities		$ 0	$ 0
Number of investments in unrealized loss position \| investment	75	75
Gross unrealized losses	$ (160,000)	$ (160,000)		$ (322,000)
Unrealized loss position, aggregate fair value	133,200,000	133,200,000
Corporate bonds [Member]
Investment [Line Items]
Gross unrealized losses	0	0		(308,000)
Unrealized loss position, aggregate fair value	117,500,000	117,500,000
U.S. Treasury and government sponsored enterprises [Member]
Investment [Line Items]
Gross unrealized losses	(28,000)	(28,000)		(14,000)
Unrealized loss position, aggregate fair value	$ 15,700,000	$ 15,700,000
Silicon Valley Bank Term Loan and Line of Credit [Member]
Investment [Line Items]
Collateral balance				$ 81,600,000