Fair Value - Summary (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value
Cash equivalents	$ 106,558	$ 110,537
Contingent consideration	8,231	3,957
Total	953,578	262,760
Blueapple
Fair Value
Redeemable non-controlling interest	702,146
eService
Fair Value
Redeemable non-controlling interest	136,643	148,266
Level 1
Fair Value
Cash equivalents	106,558	110,537
Total	106,558	110,537
Level 3
Fair Value
Contingent consideration	8,231	3,957
Total	847,020	152,223
Level 3 \| Blueapple
Fair Value
Redeemable non-controlling interest	702,146
Level 3 \| eService
Fair Value
Redeemable non-controlling interest	$ 136,643	$ 148,266

The aggregate fair value as of the reporting date of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (12)(c)
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant