Investments and Other Assets - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
Schedule of Cost-method Investments [Line Items]
Purchase of investments	$ 10,000
Colorado Corporation [Member]
Schedule of Cost-method Investments [Line Items]
Cost method investment, ownership percentage	10.00%
Purchase of investments	$ 10,000

The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

Name:	us-gaap_PaymentsToAcquireInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration