Fair Value Measurements - Total Net Gains Losses on Assets Measured at Fair Value on a Non-Recurring Basis (Details) (Non-recurring basis, Change during period, USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Impaired loans at fair value - Real estate loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses), fair value	$ 212	$ (357)	$ 1,916	$ (7,941)
Impaired loans at fair value - Commercial business
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses), fair value	(242)	(1,729)	(3,416)	(1,194)
Impaired loans at fair value - Trade finance
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses), fair value	(1,537)	0	(2,196)
Impaired loans at fair value - Consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses), fair value	195	0	149
OREO
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total gains (losses), fair value	$ (320)	$ (657)	$ (330)	$ (771)