Long-Term Debt - Debt Redemptions Percentages (Details) - Senior Unsecured Notes |
12 Months Ended |
|---|---|
Dec. 31, 2016 | |
| Redemption Period Two | |
| Debt Instrument [Line Items] | |
| Redemption price, percentage | 106.656% |
| Redemption Period Three | |
| Debt Instrument [Line Items] | |
| Redemption price, percentage | 104.438% |
| Redemption Period Four | |
| Debt Instrument [Line Items] | |
| Redemption price, percentage | 100.00% |