Organization and Summary of Significant Accounting Policies - Defined Benefit Assumption and Advertising and Marketing Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Expected long term rate of return for defined benefit plans
Time period for average rate of return	20 years
Percentage of greater of projected benefit obligation or fair value of plan assets for amortization of actuarial gains or losses	5.00%
Amortization period for actuarial gains and losses that exceed threshold	5 years
Advertising and marketing costs
Advertising and marketing	$ 4,813	$ 6,191	$ 6,127

Time period over which average rates of return on various asset classes are calculated to derive an assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

No definition available.

+ Details

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- Definition

Amortization period of amount included in accumulated other comprehensive income (AOCI) related to actuarial gain (loss) when such gains or losses exceed a percentage threshold.

+ References

No definition available.

+ Details

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- Definition

The threshold for amortization of amount included in accumulated other comprehensive income (AOCI) related to actuarial gain (loss) as a percentage of the greater of the projected benefit obligation or the fair value of plan assets.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The total expense recognized in the period for promotion, public relations, and brand or product advertising.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- References

No definition available.

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