Equity Incentive Plan - Restricted share activity (Details) - Restricted Stock [Member] - $ / shares shares in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Shares Outstanding, at beginning of the period	175
Shares Outstanding, granted	77
Shares Outstanding, vested	(58)
Shares Outstanding, forfeited	(5)
Shares Outstanding, at end of the period	189
Weighted Average Grant Date Fair Value, at beginning of the period (in dollars per share)	$ 60.53
Weighted Average Grant Date Fair Value, granted (in dollars per share)	64.56
Weighted Average Grant Date Fair Value, vested (in dollars per share)	53.96
Weighted Average Grant Date Fair Value, forfeited (in dollars per share)	64.50
Weighted Average Grant Date Fair Value, at end of the period (in dollars per share)	$ 60.53	$ 64.08

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
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-Topic 718
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-Paragraph 2
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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-SubTopic 10
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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.

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-Publisher FASB
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-Topic 718
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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.

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No definition available.

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