Convertible Subordinated Notes (Details) - USD ($)
shares in Thousands, $ in Thousands |
3 Months Ended |
6 Months Ended |
|
|
Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2017 |
Jun. 30, 2016 |
Dec. 31, 2016 |
Mar. 19, 2014 |
| Debt Instrument [Line Items] |
|
|
|
|
|
|
| Effect of dilutive securities, Convertible junior subordinated debentures (in shares) |
1,064
|
300
|
1,077
|
150
|
|
|
| Carrying Values of Liability and Equity Components, Convertible Subordinated Notes |
|
|
|
|
|
|
| Debt issuance costs |
$ (1,118)
|
|
$ (1,118)
|
|
$ (1,270)
|
|
| Accumulated Amortization, Debt Issuance Costs |
4,290
|
|
4,290
|
|
4,138
|
|
| Amortization of Debt Issuance Costs |
|
|
408
|
$ 420
|
|
|
| Convertible Subordinated Notes [Member] |
|
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
|
| Stated interest rate percentage |
|
|
|
|
|
2.75%
|
| Carrying Values of Liability and Equity Components, Convertible Subordinated Notes |
|
|
|
|
|
|
| Convertible subordinated notes, principal amount |
143,750
|
|
143,750
|
|
143,750
|
$ 143,750
|
| Unamortized discount of liability component |
(19,784)
|
|
(19,784)
|
|
(21,887)
|
|
| Debt issuance costs |
(2,011)
|
|
(2,011)
|
|
(2,268)
|
|
| Accumulated Amortization, Debt Issuance Costs |
1,616
|
|
1,616
|
|
1,359
|
|
| Carrying value of the liability component |
121,955
|
|
121,955
|
|
119,596
|
|
| Equity component carrying value |
17,973
|
|
17,973
|
|
$ 17,973
|
|
| Convertible subordinated notes, fair value |
187,600
|
|
187,600
|
|
|
|
| Contractual coupon interest expense |
1,000
|
$ 1,000
|
2,000
|
2,000
|
|
|
| Accretion of discount, convertible subordinated notes |
$ 1,100
|
$ 1,000
|
$ 2,100
|
$ 1,900
|
|
|
| Effective interest rate percentage |
2.75%
|
6.75%
|
2.75%
|
6.75%
|
|
|
| Amortization of Debt Issuance Costs |
$ 100
|
$ 100
|
$ 300
|
$ 200
|
|
|