Long-Term Debt (Interest Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Coupon interest	$ 11,240	$ 0
Amortization of debt issuance costs	1,305	0	$ 0
Total interest expense on Notes	$ 12,545	$ 0