Acquisitions - Schedule of Pro Forma Information (Details) - Discovery Benefits and Noventis $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Total revenues \| $	$ 400,982
Net income attributable to shareholders \| $	$ 18,810
Net (loss) income attributable to shareholders per share:
Basic (in dollars per share) \| $ / shares	$ 0.44
Diluted (in dollars per share) \| $ / shares	$ 0.43

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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