Loans Receivable and Allowance for Loan Losses (Residential Interest-Only Mortgage Loans, Amortization Period) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Recorded Investment
Total	$ 11,866,764	$ 12,386,378
Residential Mortgage Loans | Interest-only loans
Recorded Investment
Twelve months or less	494,856
Thirteen to twenty-four months	544,435
Twenty-five to thirty-six months	443,464
Over thirty-six months	159,342
Total	$ 1,642,097