XML 46 R35.htm IDEA: XBRL DOCUMENT v3.8.0.1
Contractual Coupon Interest Expense (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Debt Instrument [Line Items]        
Contractual coupon interest expense $ 379 $ 809 $ 1,194 $ 2,541
Accretion of discount and fees on the liability component $ 374 $ 746 $ 1,159 $ 2,288