Share-Based Payments - Textual (Details) shares in Millions	1 Months Ended
Feb. 29, 2016 shares
Restricted Stock [Member]
Share-based Compensation (Textual) [Abstract]
Restricted Stock Awards Issued	0.7
Restricted Stock Awards Issued, Service Requirement Only	0.2
Stock Options [Member]
Share-based Compensation (Textual) [Abstract]
Stock Options Granted	0.1

Under a share-based compensation plan, the number of shares of equity instruments, other than options, issued during the period to participants in the plan. Typically, these shares must meet specific performance and market conditions and service requirements before they are granted and vested to participants. These shares do not have voting rights.

No definition available.

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Namespace Prefix:	hls_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration