| **Business and Summary of Significant Accounting Principles (Business Acquisition) (Details) - USD ($)** |               | 9 Months Ended | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------|---------------|----------------|-----------------|
||
| **Noncontrolling Interest [Line Items]**                                                                 |          |           |            |
| Consideration paid                                                                                       | $ 293,200,000 |           |            |
| **Schedule of Consideration Transferred [Abstract]**                                                     |          |           |            |
| Total consideration transfered to ACS                                                                    | 304,838,000   |           |            |
| Non-controlling interest acquisition                                                                     | 303,831,000   |           |            |
| Property and equipment                                                                                   | 746,000       |           |            |
| Other intangible assets                                                                                  | 261,000       |           |            |
| Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests                              | 303,831,000   | $ 305,831,000  |            |
| Increase in Deferred Tax Assets                                                                          | 24,028,000    |           |            |
| Series of Individually Immaterial Business Acquisitions [Member]                                         |          |           |            |
| **Other Acquisitions**                                                                                   |          |           |            |
| Number of Businesses Acquired                                                                            |          |           | 3               |
| Business Combination, Consideration Transferred                                                          |          |           | $ 12,700,000    |
| Non-controlling Interests [Member]                                                                       |          |           |            |
| **Schedule of Consideration Transferred [Abstract]**                                                     |          |           |            |
| Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests                              | 268,364,000   | 271,521,000    |            |
| Additional Paid-in Capital [Member]                                                                      |          |           |            |
| **Schedule of Consideration Transferred [Abstract]**                                                     |          |           |            |
| Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests                              | $ 11,439,000  | 34,310,000     |            |
| Other Nonoperating Income (Expense) [Member] | Rights to Receive Future Capacity [Member]                |          |           |            |
| **Noncontrolling Interest [Line Items]**                                                                 |          |           |            |
| Fair value adjustment to assets                                                                          |          | 1,200,000      |            |
| Other Nonoperating Income (Expense) [Member] | Rights to Use Capacity [Member]                           |          |           |            |
| **Noncontrolling Interest [Line Items]**                                                                 |          |           |            |
| Impairment of intangible assets                                                                          |          | $ 3,800,000    |            |

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Fair Value of Consideration for Non-Controlling Interest
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Increase in Deferred Tax Assets from purchase of noncontrolling interest
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| - Definition
Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.
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| - Definition
Amount of gain (loss) on sale or disposal of intangible assets.
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| - Definition
The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.
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| - Definition
Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).
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The number of businesses acquired by the entity during the period.
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| - Definition
The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.
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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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