Long-Term Debt - Debt (Details) - USD ($)
|
Dec. 31, 2016 |
Dec. 31, 2015 |
Feb. 17, 2007 |
| Debt Instrument [Line Items] |
|
|
|
| Long-term debt |
$ 161,349,000
|
$ 47,120,000
|
|
| Less current maturities of long-term debt |
(15,261,000)
|
(2,028,000)
|
|
| Long-term debt of current maturities |
146,088,000
|
45,092,000
|
|
| Convertible Subordinated Debt | Convertible Senior Notes at 5.00% February 2021 [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
150,000,000
|
|
|
| Long-term debt |
115,159,000
|
0
|
|
| Debt Instrument, Unamortized Discount |
29,919,000
|
|
|
| Debt Instrument, Fee Amount, Net Balance Shown as a Liability |
(4,922,000)
|
|
|
| Debt Instrument, Net Carrying Amount |
115,159,000
|
|
|
| Convertible Subordinated Debt | Convertible senior subordinated debentures at 4.125%, due in February 2027 |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
|
|
$ 135,000,000
|
| Long-term debt |
13,039,000
|
12,147,000
|
|
| Debt Instrument, Unamortized Discount |
311,000
|
1,203,000
|
|
| Other notes and lease obligations |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Long-term debt |
33,151,000
|
34,973,000
|
|
| Revolving Credit Facility due 2018 [Member] | Line of Credit |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Long-term debt |
$ 0
|
$ 0
|
|