XML 58 R69.htm IDEA: XBRL DOCUMENT
v3.20.1

Preferred and Common Stockholder's Equity - Schedule of Stock Repurchases (Detail) - USD ($) shares in Millions, $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Jun. 30, 2019
Stockholders Equity [Line Items] |  |
Shares purchased and retired |  | 1.6
Common stock and additional paid-in-capital reductions | $ 16.9 |
Charges to retained earnings | $ 33.1 |
Common Stock [Member] |  |
Stockholders Equity [Line Items] |  |
Shares purchased and retired | 1.6 |

X
- Definition Amount charged to retained earnings as a result of stock repurchases. + References No definition available. + Details
Name: | mygn_AmountChargedToRetainedEarningsAsResultOfStockRepurchases
Namespace Prefix: | mygn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of reduction in common stock as a result of stock repurchases. + References No definition available. + Details
Name: | mygn_AmountOfReductionInCommonStockAsResultOfStockRepurchases
Namespace Prefix: | mygn_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Stockholders Equity [Line Items] + References No definition available. + Details
Name: | mygn_StockholdersEquityLineItems
Namespace Prefix: | mygn_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares that have been repurchased and retired during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 + Details
Name: | us-gaap_StockRepurchasedAndRetiredDuringPeriodShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |