Commitments and Contingencies (Narrative) (Details)	6 Months Ended
Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Percentage of capital committed to strategic investments that may be drawn down	100.00%

Represents the percentage of capital committed to strategic investments by the entity that may be drawn down.

No definition available.

Name:	star_PercentageOfCapitalCommittedThatMayBeDrawnDown
Namespace Prefix:	star_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration