Variable Interest Entities (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Variable Interest Entities
Affordable housing investments	$ 200,570,000	$ 188,207,000
Affordable Housing VIEs - not primary beneficiary
Variable Interest Entities
Affordable housing investments	200,600,000	188,200,000
Unfunded commitments for affordable housing investments	77,100,000
Number of significant variable interest in affordable housing partnerships (in entities)	4
Maximum exposure to loss	1,000,000
Unfunded commitments for affordable housing investments with significant variable interest	0
Aggregate carrying value of private equity and alternative investment funds	$ 29,700,000	$ 34,000,000