Available For Sale Securities Debt Maturities Within One Year Gross Unrealized Gain

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- Definition

Available For Sale Securities Debt Maturities Within One Year Gross Unrealized Losses

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No definition available.

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- Definition

Available-for-sale Securities, Debt Maturities, Year Two Through Five, Gross Unrealized Gain

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- Definition

Available-for-sale Securities, Debt Maturities, Year Two Through Five, Gross Unrealized Loss

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- Definition

This item represents the aggregate of cash and cash equivalents and the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified neither as held-to-maturity nor trading securities.

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No definition available.

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- Definition

Represents cash, cash equivalents and marketable securities, gross unrealized gains as on the reporting date.

+ References

No definition available.

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Represents cash, cash equivalents and marketable securities, gross unrealized losses.

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No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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- Definition

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

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-Publisher FASB
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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.

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-Publisher FASB
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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- Definition

Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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No definition available.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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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.

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No definition available.

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Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash, Cash Equivalents and Marketable Securities:
Cash, money market funds, amortization cost	$ 73,651	$ 150,738	$ 61,461	$ 61,349
Cash, money market funds, fair value	73,651	150,738
Cash, cash equivalents and marketable securities, amortized cost	380,030	353,065
Cash, cash equivalents and marketable securities, gross unrealized gains	69	136
Cash, cash equivalents and marketable securities, gross unrealized losses	(209)	(50)
Cash, cash equivalents and marketable securities, fair value	379,890	353,151
Marketable securities, amortized cost	306,379	202,327
Marketable securities, gross unrealized gains	69	136
Marketable securities, gross unrealized losses	(209)	(50)
Marketable securities, fair value	306,239	202,413
Cash, money market funds and overnight repurchase agreements
Cash, Cash Equivalents and Marketable Securities:
Cash, money market funds, amortization cost	73,651	150,738
Cash, money market funds, fair value	73,651	150,738
U.S. government-sponsored enterprise securities
Cash, Cash Equivalents and Marketable Securities:
Available for sale securities, amortized cost	18,186
Available for sale securities, gross unrealized gains	0
Available for sale securities, gross unrealized losses	(5)
Available for sale securities, fair value	18,181
Corporate debt securities
Cash, Cash Equivalents and Marketable Securities:
Available for sale securities, amortized cost	118,541	47,942
Available for sale securities, gross unrealized gains	3	0
Available for sale securities, gross unrealized losses	(115)	(36)
Available for sale securities, fair value	118,429	47,906
Available-for-sale securities, due in more than one year, amortized cost	30,487
Available-for-sale securities, due in more than one year, gross unrealized gains	1
Available-for-sale securities, due in more than one year, gross unrealized losses	(43)
Available-for-sale securities, due in more than one year, fair value	30,445
Certificates of deposit
Cash, Cash Equivalents and Marketable Securities:
Available for sale securities, amortized cost	6,501
Available for sale securities, gross unrealized gains	0
Available for sale securities, gross unrealized losses	0
Available for sale securities, fair value	6,501
Available-for-sale securities, due in more than one year, amortized cost	1,297
Available-for-sale securities, due in more than one year, gross unrealized gains	0
Available-for-sale securities, due in more than one year, gross unrealized losses	(4)
Available-for-sale securities, due in more than one year, fair value	1,293
Commercial paper obligations
Cash, Cash Equivalents and Marketable Securities:
Available for sale securities, amortized cost	108,573	84,301
Available for sale securities, gross unrealized gains	65	135
Available for sale securities, gross unrealized losses	(8)	0
Available for sale securities, fair value	108,630	84,436
Asset-backed securities
Cash, Cash Equivalents and Marketable Securities:
Available for sale securities, amortized cost	17,307	70,084
Available for sale securities, gross unrealized gains	0	1
Available for sale securities, gross unrealized losses	(30)	(14)
Available for sale securities, fair value	17,277	$ 70,071
Available-for-sale securities, due in more than one year, amortized cost	5,487
Available-for-sale securities, due in more than one year, gross unrealized gains	0
Available-for-sale securities, due in more than one year, gross unrealized losses	(4)
Available-for-sale securities, due in more than one year, fair value	$ 5,483