Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Share-based compensation (Narrative) (Details)

v3.8.0.1
Share-based compensation (Narrative) (Details)
$ in Thousands
1 Months Ended 12 Months Ended
Dec. 31, 2015
Dec. 31, 2017
USD ($)
shares
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
May 14, 2014
shares
Share-Based Compensation [Line Items]          
Share based compensation expense | $   $ 107,719 $ 102,843 $ 100,162  
Equity Incentive Plan 2012          
Share-Based Compensation [Line Items]          
Equity awards available for grants (in shares)         8,064,081
Equity Incentive Plan 2014          
Share-Based Compensation [Line Items]          
Equity awards available for grants (in shares)         4,500,000
NV Equity Plan          
Share-Based Compensation [Line Items]          
Restricted stock units convertible to common shares, conversion ratio 1        
NV Equity Plan | Time Based and Performance Based Restricted Stock Units And Restricted Stocks [Member]          
Share-Based Compensation [Line Items]          
Overlap of equity awards vested and expected to vest included in shares outstanding (in shares)   6,500,000      
NV Equity Plan | Minimum [Member]          
Share-Based Compensation [Line Items]          
Equity award vesting period   3 years      
NV Equity Plan | Maximum [Member]          
Share-Based Compensation [Line Items]          
Equity award vesting period   5 years