v3.8.0.1

Summary of Significant Accounting Policies - Schedule Of Amortization Period For Intangible Assets (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	11 years 7 months 6 days	11 years 6 months
Purchased contract rights
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	12 years 7 months 6 days	12 years 7 months 6 days
Purchased contract rights | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	5 years
Purchased contract rights | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Provider contracts
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	11 years 10 months 24 days	10 years 8 months 12 days
Provider contracts | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	4 years
Provider contracts | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	8 years 2 months 12 days	8 years 2 months 12 days
Customer relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	3 years
Customer relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	15 years
Trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	9 years 7 months 6 days	9 years 7 months 6 days
Trade names | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	7 years
Trade names | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	20 years
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization period	5 years	5 years

X

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- 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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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X

- Details

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Namespace Prefix:
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Balance Type:
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X

- Details

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Period Type:

X

- Details

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Period Type:

X

- Details

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X

- Details

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X

- Details

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Period Type:

X

- Details

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Namespace Prefix:
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Period Type: