Intangible Assets	3 Months Ended
Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Accumulated amortization of intangible assets was $27.5 million and $27.0 million at March 31, 2018 and December 31, 2017, respectively.

The entire disclosure for all or part of the information related to intangible assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-URI http://asc.fasb.org/topic&trid=2144416

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