Leases - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Lessee Lease Description [Line Items]
Residual value of leased asset	$ 3.7
Minimum [Member]
Lessee Lease Description [Line Items]
Remaining lease term, operating lease	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Remaining lease term, operating lease	7 years

Amount of residual asset covered by residual value guarantee under operating lease. Excludes guarantee considered to be lease payments for lessor.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981

Name:	us-gaap_OperatingLeaseResidualValueOfLeasedAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant