Income Taxes (Unrecognized tax benefits - rollforward and discussion) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, beginning of period	$ 27,211	$ 23,149	$ 23,332
Additions based on tax positions related to the current year	401	1,419	1,822
Additions for tax positions of prior years	636	2,661	689
Reductions for tax positions of prior years	(2,958)	(1)	(2,589)
Reductions from lapse of statutes of limitations	(22)	(17)	(105)
Balance, end of period	25,268	$ 27,211	$ 23,149
Income tax contingency [Abstract]
Unrecognized tax benefits, period increase (decrease)	1,900
Liability for uncertain tax positions	25,300
Accrued and unpaid interest and penalties	$ 5,300