Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount of unrealized gain (loss) on investment in marketable security.

+ References

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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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.

+ References

No definition available.

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Recently Adopted Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Apr. 30, 2018	Jun. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Marketable securities		$ 1,737	$ 1,737
Corporate Owned Life Insurance Policy [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Amount sold of available-for-sale marketable securities	$ 2,900	3,000
ASU 2016-18 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
New accounting pronouncement or change in accounting principle, cumulative effect of change on equity or net assets		$ 300	300		$ 1,200
ASU 2016-01 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Marketable securities				$ 4,300
ASU 2016-01 [Member] \| Maximum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Gain on change in fair value of marketable securities			$ 100