Business Combination - Estimated Acquisition Date Fair Value of the Consideration Transferred (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
Jul. 01, 2013	Oct. 24, 2012
Ambrose Employer Group, LLC (Ambrose)
Business Acquisition [Line Items]
Cash paid to equity holders	$ 201,271
Cash and cash equivalents acquired	(6,273)
Total	194,998
SOI Holdings Inc
Business Acquisition [Line Items]
Cash paid to equity holders		198,171
Receivable from equity holders		(1,893)
Cash and cash equivalents acquired		(504)
Total		$ 195,774

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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The amount of assets that an Entity acquires in a noncash (or part noncash) acquisition that are not presented as a separate disclosure or not otherwise listed in the existing taxonomy. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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