Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions		6 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income attributable to Myriad Genetics, Inc. stockholders		$ 1.9	$ 109.7	[1]
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization		36.3	26.3	[1]
Non-cash interest expense		(1.2)	0.1	[1]
Loss (gain) on disposition of assets		(0.9)	0.1	[1]
Share-based compensation expense		15.2	13.3	[1]
Deferred income taxes		2.3	(25.9)	[1]
Unrecognized tax benefits		(2.3)	8.2	[1]
Change in fair value of contingent consideration		(1.4)	(60.2)	[1]
Changes in assets and liabilities:
Prepaid expenses		0.8	2.9	[1]
Trade accounts receivable		(0.9)	(13.0)	[1]
Other receivables		(1.9)	1.4	[1]
Inventory		6.1	4.1	[1]
Prepaid taxes		(3.1)	(8.4)	[1]
Accounts payable		(0.3)	3.0	[1]
Accrued liabilities		(4.7)	(5.8)	[1]
Deferred revenue		(0.3)	0.7	[1]
Net cash provided by operating activities		45.6	56.5	[1]
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures		(4.1)	(3.7)	[1]
Acquisitions, net of cash acquired		(278.5)
Purchases of marketable investment securities		(36.6)	(61.3)	[1]
Proceeds from maturities and sales of marketable investment securities		32.1	45.2	[1]
Net cash used in investing activities		(287.1)	(19.8)	[1]
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from common stock issued under share-based compensation plans		4.5	6.3	[1]
Net proceeds from revolving credit facility		340.0
Repayment of revolving credit facility		(75.0)	(56.0)	[1]
Repurchase and retirement of common stock		(50.0)
Proceeds from non-controlling interest	[1]		0.3
Net cash provided by (used in) financing activities		219.5	(49.4)	[1]
Effect of foreign exchange rates on cash and cash equivalents		1.7	(1.0)	[1]
Net decrease in cash and cash equivalents		(20.3)	(13.7)	[1]
Cash and cash equivalents at beginning of the period	[1]	110.9	102.4
Cash and cash equivalents at end of the period		$ 90.6	$ 88.7	[1]

[1] Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part I, Item 1 of this report for additional information.