Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

No definition available.

Name:	us-gaap_GoodwillAndIntangibleAssetImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Goodwill, Intangible Assets and Impairment Charges - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 01, 2017
Goodwill And Intangible Assets [Line Items]
Impairment of goodwill and intangible assets	$ 0	$ 0	$ 0
Minimum
Goodwill And Intangible Assets [Line Items]
Reporting unit in excess of carrying value				20.00%