XML 41 R29.htm IDEA: XBRL DOCUMENT v3.19.1
Summary of Significant Accounting Policies - Additional Information (Detail)
$ in Millions
3 Months Ended
Mar. 31, 2019
USD ($)
Accounting Standards Update 2016-02 Leases (Topic 842)  
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]  
Impact of new lease accounting standard on assets and liabilities $ 2.1