Schedule II -- Valuation and Qualifying Accounts (Consolidated) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Doubtful Accounts & Discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		$ 7,066	$ 5,586	$ 5,846
Charged to expense or other accounts		1,118	2,719	1,040
Deductions	[1]	(352)	(1,239)	(1,300)
Balance at end of period		7,832	7,066	5,586
Valuation Allowance for Deferred Tax Asset
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		11,184	66,486	46,048
Charged to expense or other accounts		2,589	6,093	21,420
Deductions	[2]	0	(61,395)	(982)
Balance at end of period		$ 13,773	$ 11,184	$ 66,486

[1] Uncollectible accounts written off, net of recoveries.

[2] The net decrease in valuation allowance is primarily a result of net changes in cumulative book/tax timing differences and, with respect to activity for the year ended December 31, 2015, changes in judgment regarding the realizability of U.S. deferred tax assets.