Business Acquisitions (Details) - USD ($) $ in Thousands	Jul. 01, 2016	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Less:
Goodwill		$ 188,184	$ 188,184	$ 56,342
HealthiestYou
Business acquisition
Purchase price	$ 151,500
Equity consideration (in shares)	6,955,796
Equity consideration	$ 108,300
Cash paid for acquisition	43,200
Transaction costs associated with acquisition	6,900
Contract termination costs associated with acquisition	5,700
Identifiable assets acquired and liabilities assumed:
Purchase price	151,484
Less:
Cash	6,204
Accounts receivable	1,184
Other assets	1,537
Accounts payable	(836)
Other liabilities	(2,847)
Goodwill	131,842
HealthiestYou | Maximum
Business acquisition
Adjustments for working capital	100
HealthiestYou | Client relationships
Less:
Finite-lived intangibles	10,930
HealthiestYou | Non-compete agreements
Less:
Finite-lived intangibles	70
HealthiestYou | Internal-Use Software
Less:
Finite-lived intangibles	2,220
HealthiestYou | Trademarks
Less:
Finite-lived intangibles	$ 1,180