| Equity and Long-Term Incentive Compensation Plans  - Cash Long-Term Incentive Plan (Details) - Cash long-term incentive plan $ in Millions | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Mar. 31, 2016  USD ($) | Mar. 31, 2015  USD ($) | Mar. 31, 2016  USD ($)  vesting_installment | Mar. 31, 2015  USD ($) | |
| Cash Long-Term Incentive Plan | ||||
| Cash-based long-term incentive plan, approved amount | $ 47.8 | $ 66.7 | $ 47.8 | $ 66.7 | 
| Cash long-term incentive plan, number of equal vesting installments | vesting_installment | 4 | |||
| Cash long-term incentive plan, percentage of equal vesting installments (as a percent) | 25.00% | |||
| Cash long-term incentive plan, vesting period (in years) | 4 years | |||
| Cash long-term incentive program, compensation expense | 11.6 | $ 10.5 | $ 33.0 | $ 29.0 | 
| Cash long-term incentive plan, unrecognized compensation balance | $ 100.5 | $ 100.5 | ||
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- Definition Deferred Compensation Arrangement with Individual, Number of Equal Vesting Installments No definition available. 
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- Definition Deferred Compensation Arrangement with Individual, Percentage Of Equal Vesting Installments No definition available. 
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- Definition Deferred Compensation Arrangement With Individual, Unrecognized Compensation Liability No definition available. 
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- Definition Deferred Compensation Arrangement with Individual, Vesting Period No definition available. 
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- Definition Long-Term Incentive Plan, Approved Amount No definition available. 
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- Definition The compensation expense recognized during the period pertaining to the deferred compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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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. No definition available. 
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- Details 
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