Schedule II - Valuation And Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance For Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
BALANCE AT BEGINNING OF PERIOD	$ (12,590)	$ (10,892)	$ (11,524)
(CHARGED) CREDITED TO COSTS AND EXPENSES	(13,079)	(10,690)	(9,233)
(CHARGED) CREDITED TO OTHER ACCOUNTS	(840)	(1,318)	(1,326)
DEDUCTIONS	11,781	10,310	11,191
BALANCE AT END OF PERIOD	(14,728)	(12,590)	(10,892)
Allowance For Doubtful Accounts - Notes Receivable [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
BALANCE AT BEGINNING OF PERIOD	(378)	(132)	(305)
(CHARGED) CREDITED TO COSTS AND EXPENSES	(94)	(217)	122
(CHARGED) CREDITED TO OTHER ACCOUNTS	(33)	(29)	51
BALANCE AT END OF PERIOD	$ (505)	$ (378)	$ (132)

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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