Common Stock - Summary of Restricted Stock Unit Award Activity (Detail) - Restricted Stock Unit [Member] |
12 Months Ended |
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Dec. 31, 2019
$ / shares
shares
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| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
| Number of Shares, Beginning Balance | shares | 15,142 |
| Number of Shares, Released | shares | (5,134) |
| Number of Shares, Ending Balance | shares | 10,008 |
| Weighted-Average Grant Date Fair Value, Beginning Balance | $ / shares | $ 30.53 |
| Weighted-Average Grant Date Fair Value, Released | $ / shares | 33.54 |
| Weighted-Average Grant Date Fair Value, Ending Balance | $ / shares | $ 28.99 |
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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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- Details
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