Description of Business and Significant Accounting Policies (Details) - USD ($) $ in Millions	Jan. 01, 2017	Jun. 30, 2017
Assets under management		$ 80,400.0
ASU 2016-09
Increase to additional paid-in capital	$ 3.5
Reduction to retained earnings	(2.2)
Increase to the non-current deferred tax asset	$ 1.3

Amount after income tax of income (loss) including the portion attributable to nonredeemable noncontrolling interest. Excludes the portion attributable to redeemable noncontrolling interest recognized as temporary equity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684

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

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