Valuation and Qualifying Accounts and Reserves (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 190	$ 200	$ 200
Charged to expense	430	399	504
Accounts written off	(650)	(675)	(681)
Recoveries of accounts written off	302	266	177
Ending Balance	272	190	200
SEC Schedule, 12-09, Reserve, Legal [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	1,892	2,105	263
Charged to expense	480	528	2,186
Accounts written off	1	(245)	(19)
Payments	(192)	(496)	(325)
Ending Balance	$ 2,181	$ 1,892	$ 2,105

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

+ Details

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from recovery of amount previously written off or reestablishment of reserve previously utilized.

+ References

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