Cash, cash equivalents and available-for-sale securities valued at fair value.

No definition available.

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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.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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- Definition

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.

+ 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 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3044-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

Reference 5: 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

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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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Cash Equivalents and Investments (Summary of Cash and Available-For-Sale Securities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-For-Sale Securities [Line Items]
Adjusted Cost	$ 167,141	$ 219,682
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	670
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	167,141	220,352
Cash and Cash Equivalents	147,154	218,883	$ 291,377	$ 94,302
Short-Term Marketable Securities	19,987	1,469
Cash [Member]
Schedule of Available-For-Sale Securities [Line Items]
Adjusted Cost	147,150	124,082
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	147,150	124,082
Cash and Cash Equivalents	147,150	124,082
Short-Term Marketable Securities	0	0
Money Market Funds [Member]
Schedule of Available-For-Sale Securities [Line Items]
Adjusted Cost	4	94,801
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	4	94,801
Cash and Cash Equivalents	4	94,801
Short-Term Marketable Securities	0	0
Equity Securities [Member]
Schedule of Available-For-Sale Securities [Line Items]
Adjusted Cost		799
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		670
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	0	1,469
Cash and Cash Equivalents		0
Short-Term Marketable Securities		$ 1,469
Commercial Paper [Member]
Schedule of Available-For-Sale Securities [Line Items]
Adjusted Cost	19,987
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	19,987
Cash and Cash Equivalents	0
Short-Term Marketable Securities	$ 19,987