Employee Benefit Plans - Restricted shares and units (Details) - Restricted Stock Units (RSUs) [Member] - Discontinued Operations [Member] - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary of aggregate activity of restricted shares and units
Stock Units, Outstanding Beginning of year	1,107,315
Stock Units, Granted	64,063
Stock Units, Forfeited / Cancelled	(2,307)
Stock Units, Issued	(177,163)
Stock Units, Outstanding End of year	991,908	1,107,315
Weighted-Average Grant-Date Fair Value, beginning of year	$ 46.57
Weighted-Average Grant-Date Fair Value, Granted	63.58
Weighted-Average Grant-Date Fair Value, Forfeited / Cancelled	23.73
Weighted-Average Grant-Date Fair Value, Issued	49.23
Weighted-Average Grant-Date Fair Value, ending of year	$ 47.24	$ 46.57
Total Fair Value, Issued	$ 11,000,000	$ 17,000,000	$ 4,000,000
Employee Benefit Plans Additional (Textual) [Abstract]
Unrecognized compensation cost from stock options	0
Weighted-Average Grant-Date Fair Value, granted		$ 62.01	$ 48.87
Total Fair Value, Issued	$ 11,000,000	$ 17,000,000	$ 4,000,000

Employee benefit plans.

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Share based compensation arrangement by share based payment award equity instruments other than options grants in period weighted average grant date fair value.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options,

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- Definition

Summarizes the aggregate activity of these restricted shares and units.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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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.

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- Definition

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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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).

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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