Amount of cost for defined contribution plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

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Employee Benefits - Defined Contribution (Details) - USD ($)	2 Months Ended	10 Months Ended	12 Months Ended
	Dec. 31, 2017	Oct. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, maximum annual contribution per employee	$ 18,000		$ 19,000	$ 18,500
Defined contribution plan, cost	7,000,000	$ 30,000,000	$ 29,000,000	26,000,000
Defined Contribution Plan, Contribution Level 1
Defined Contribution Plan Disclosure [Line Items]
Percent of match			100.00%
Defined contribution plan, employer matching contribution, percentage			1.00%
Defined Contribution Plan, Contribution Level 2
Defined Contribution Plan Disclosure [Line Items]
Percent of match			60.00%
All Other Defined Contribution
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, cost	1,000,000	5,000,000	$ 6,000,000	5,000,000
Cost of services and products
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, cost	1,000,000	4,000,000	11,000,000	10,000,000
Selling, general and administrative expense
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, cost	$ 5,000,000	$ 26,000,000	$ 18,000,000	$ 16,000,000
Minimum \| Defined Contribution Plan, Contribution Level 2
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution, percentage			1.00%
Maximum \| Defined Contribution Plan, Contribution Level 2
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution, percentage			6.00%