v3.8.0.1

Subsequent events	12 Months Ended
	Dec. 31, 2017
Subsequent events
Subsequent events	18. Subsequent events Equity Incentive Plan         In February 2018, we granted approximately 44,000 time-based RSUs to certain executive officers that vest quarterly over three years of continuous service and approximately 44,000 performance-based RSUs (assuming at-target achievement) that vest upon achievement of performance objectives through December 31, 2019. 662/3% of the performance-based RSUs will vest on a determination date not to exceed March 15, 2020, another 81/3% will vest on May 1, 2020, and an additional 81/3% will vest quarterly thereafter upon completion of continuous service.         We also granted approximately 168,000 time-based RSUs to non-executive personnel that will vest quarterly over three years of continuous service.         The grants were made pursuant to our 2011 Plan.

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- Definition

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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