Loan Loss Allowance and Credit Quality - Summary of Activity in Loan Loss Allowance Related to Purchased Receivables Portfolios (Details) (Purchased Receivables Portfolios, USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Purchased Receivables Portfolios
Allowance for Loan and Lease Losses [Roll Forward]
Balance — beginning of period	$ 206,170	$ 184,192	$ 226,356	$ 218,640
Incremental provisions for purchased receivable portfolios	350	18,314	1,675	39,976
Incremental reversal of provisions for purchased receivable portfolios	(8,676)	(25,930)	(30,187)	(82,040)
Balance — end of period	$ 197,844	$ 176,576	$ 197,844	$ 176,576