XML 57 R26.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Schedule of Fair Value for Available-for-Sale Securities by Major Security Type and Class of Security (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 | Jun. 30, 2013
--- | --- | ---
Net Investment Income [Line Items] |  |
Amortized cost | $ 277,378 | $ 531,497
Gross unrealized holding gains | 346 | 154
Gross unrealized holding losses | (11) | (587)
Estimated fair value | 277,713 | 531,064
Cash |  |
Net Investment Income [Line Items] |  |
Amortized cost | 82,536 | 40,412
Estimated fair value | 82,536 | 40,412
Cash Equivalents |  |
Net Investment Income [Line Items] |  |
Amortized cost | 3,262 | 63,653
Gross unrealized holding gains |  | 8
Estimated fair value | 3,262 | 63,661
Total Cash And Cash Equivalents |  |
Net Investment Income [Line Items] |  |
Amortized cost | 85,798 | 104,065
Gross unrealized holding gains |  | 8
Estimated fair value | 85,798 | 104,073
Corporate Bonds And Notes |  |
Net Investment Income [Line Items] |  |
Amortized cost | 49,396 | 71,626
Gross unrealized holding gains | 43 | 13
Gross unrealized holding losses | (3) | (15)
Estimated fair value | 49,436 | 71,624
Municipal Bonds |  |
Net Investment Income [Line Items] |  |
Amortized cost | 123,997 | 251,513
Gross unrealized holding gains | 286 | 109
Gross unrealized holding losses | (8) | (537)
Estimated fair value | 124,275 | 251,085
Federal Agency Issues |  |
Net Investment Income [Line Items] |  |
Amortized cost | 18,187 | 104,293
Gross unrealized holding gains | 17 | 24
Gross unrealized holding losses |  | (35)
Estimated fair value | 18,204 | 104,282
Total Available For Sale |  |
Net Investment Income [Line Items] |  |
Amortized cost | 191,580 | 427,432
Gross unrealized holding gains | 346 | 146
Gross unrealized holding losses | (11) | (587)
Estimated fair value | $ 191,915 | $ 426,991

X
- Definition Amount of accumulated pre-tax unrealized gain before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments. + References No definition available. + Details
Name: | mygn_AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments
Namespace Prefix: | mygn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale securities impacting investments. + References No definition available. + Details
Name: | mygn_AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments
Namespace Prefix: | mygn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration