Income Taxes (Unrecognized tax benefits - rollforward and discussion) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	$ 23,332	$ 12,670	$ 27,128
Additions based on tax positions related to the current year	1,822	12,727	6,032
Additions for tax positions of prior years	689	3,341	1,240
Reductions for tax positions of prior years	(2,589)	(4,815)	(15,433)
Reductions related to settlements with tax authorities	0	0	(6,297)
Reductions from lapse of statutes of limitations	(105)	(591)	0
Balance, end of period	23,149	$ 23,332	$ 12,670
Income tax contingency [Abstract]
Unrecognized tax benefits, period increase (decrease)	(200)
Decrease in unrecognized tax benefits as a result of positive ruling on the tax treatment of an expense	2,000
Liability for uncertain tax positions	21,300
Accrued and unpaid interest and penalties	$ 2,500