Benefit Plans - Additional Information (Detail)	12 Months Ended
Dec. 31, 2018
Defined Contribution Plan Disclosure [Line Items]
Percentage of participant directed contributions to benefit plans	100.00%
Maximum
Defined Contribution Plan Disclosure [Line Items]
Participants contribution percentage allowed to invest in Company's common stock	10.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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