Significant Accounting Policies (Details)	12 Months Ended
Dec. 31, 2016 category deliverable
Revenue recognition [Line items]
Maximum period of customer obligations (in years)	1 year
Number of deliverables per unit of accounting for deferral of all revenue, greater than \| deliverable	1
Number of categories for each segment in which total revenues are reported \| category	2
Unconsolidated real estate affiliates
Investments [Line Items]
Equity Method Investment, Ownership Percentage	50.00%

Represents the maximum period of the entity's customer obligations in connection with goods and services provided.

No definition available.

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Namespace Prefix:	dst_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of categories for each segment in which the entity's total revenues are reported.

+ References

No definition available.

+ Details

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Namespace Prefix:	dst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

For units of accounting with more than this number of deliverables, all revenues are deferred until the period over which the last undelivered item is delivered.

+ References

No definition available.

+ Details

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Namespace Prefix:	dst_
Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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