Goodwill, Core Deposit Premium and Other Intangible Assets (Changes in capitalized mortgage servicing rights) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	$ 15,653	$ 11,276
Originations	3,245	1,986
Amortization	(1,761)	(1,719)
Valuation adjustment	496	13
Balance at end of period	$ 17,633	$ 11,556

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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- Definition

Amortized carrying amount (balance) as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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