Consolidated Variable Interest Entities - Number of FG VIE's Consolidated (Details) - Variable Interest Entity, Primary Beneficiary [Member] - Entity	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Number of FG VIEs Consolidated [Roll Forward]
Number of FG VIE's consolidated, beginning of period	32	34
Number of FG VIE's consolidated	1	0
Number of FG VIE's deconsolidated	(1)	(1)
Number of FG VIE's Matured	0	(1)
Number of FG VIE's consolidated, end of period	32	32