Schedule II - Valuation and Qualifying Accounts (Details) - Valuation and Qualifying Accounts (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	$ 10,771	$ 16,402	$ 18,059
Charged to expenses	3,886	3,521	6,309
Deductions	(4,289)	(9,152)	(7,966)
Balance at end of period	10,368	10,771	16,402
Valuation Allowance of Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Balance at beginning of period	63,712	71,912	66,520
Adjustments to valuation accounts	(29,410)	(8,200)	5,392
Balance at end of period	$ 34,302	$ 63,712	$ 71,912

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Total of the adjustments in a given period to 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.

+ References

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

+ Details

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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.

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Total of the deductions in a given period to 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, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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