Variable Interest Entities - Additional Information (Details) $ in Thousands	Dec. 31, 2016 USD ($) entity	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Variable Interest Entity [Line Items]
Amortization method qualified affordable housing project investments	$ 112,447	$ 154,356
Qualified Affordable Housing Project Investments, Commitment	58,095	90,978
Total assets	(44,683,660)	(44,686,703)
Total equity	$ (3,777,037)	(3,333,231)	$ (4,051,734)	$ (3,074,693)
Number of consolidated entities | entity	5
Maximum Exposure to Loss in Unconsolidated VIEs	$ 314,810	364,450
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Total assets	(314,810)	(364,450)
Accrued expenses and other liabilities	58,095	90,978
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Total assets	(207,903)	(216,019)
Accrued expenses and other liabilities	517	$ 433
Maximum Exposure to Loss in Unconsolidated VIEs	$ 207,400