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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2015
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) | $ 4.9 | $ (2.2) |
Net deferred tax liabilities | 177.7 | 81.1 |
Tax deficiency realized | 3.1 |  |
Share-based compensation tax benefits |  | 12.7 | $ 3.4
Excess tax benefits attributable to deferred tax asset | 75.5 | 54.4 |
Deferred tax liability not recognized, Amount of unrecognized deferred tax liability, undistributed earnings of foreign subsidiaries | 0.0 |  |
Cumulative effect | $ 0.0 |  |
Income tax returns examination | The Company’s income tax returns for the following jurisdictions are currently under examination: California State income tax returns for the years ended June 30, 2013 through 2014; New Jersey State income tax returns for the years ended June 30, 2007 through 2013; and U.S. income tax returns for the years ended June 30, 2014 through 2015. The Company recently was subject to an examination of its payroll reporting by the Internal Revenue Service. The payroll audit concluded during the year ended June 30, 2017 and resulted in a penalty of $0.9, which is included in the Company’s results for that year. |  |
Payroll audit resulted in penalty | $ (0.9) | 0.5 | $ 0.6
New Accounting Pronouncement, Adoption Effect [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) |  | 3.8 |
Prior to the adoption of Statement 123(R) [Member] | UTAH [Member] |  |  |
Income Taxes [Line Items] |  |  |
Excess tax benefits attributable to deferred tax asset | 6.8 |  |
State Research Tax Credit Carryforward [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) |  | 1.9 |
Foreign Net Operating Losses [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) |  | $ (3.5) |
UTAH [Member] | Research Activities Credits [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) | 0.4 |  |
Assurex [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) | 1.9 |  |
Net deferred tax liabilities | 64.5 |  |
Sividon Diagnostics GmbH [Member] |  |  |
Income Taxes [Line Items] |  |  |
Net deferred tax liabilities | 13.2 |  |
Capital Losses [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) | 1.4 |  |
Foreign Losses [Member] |  |  |
Income Taxes [Line Items] |  |  |
Amount of valuation allowance increased (decreased) | $ 1.2 |  |

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