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
Changes in valuation and qualifying accounts
Balance at Beginning of Year	$ 695	$ 506	$ 485
Additions Charged to Costs and Expenses	745	574	492
Reductions	(488)	(385)	(471)
Balance at End of Year	952	695	506
Tax valuation account
Changes in valuation and qualifying accounts
Balance at Beginning of Year	21,340	25,299	318
Acquired through Central Merger			24,981
Additions Charged to Costs and Expenses		2,075
Reductions	(9,048)	(6,034)
Balance at End of Year	$ 12,292	$ 21,340	$ 25,299

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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.

+ 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

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