Investments (Tables)

3 Months Ended

Mar. 31, 2014

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments

At March 31, 2014 investments classified as available-for-sale securities were as follows:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities:
U.S. Treasury securities	$	224,826	$	16	$	—	$	224,842
Corporate debt securities	56,244		—		2,669		53,575
Preferred stock	3,270		103		—		3,373
	$	284,340	$	119	$	2,669	$	281,790

At December 31, 2013 investments classified as available-for-sale securities were as follows:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Debt securities:
U.S. Treasury securities	$	124,861	$	88	$	—	$	124,949
Corporate debt securities	24,236		—		2,213		22,023
	$	149,097	$	88	$	2,213	$	146,972

Contractual Maturities of Investments

The net carrying value and estimated fair value of investments classified as available-for-sale at March 31, 2014, by contractual maturity are shown in the following table. Actual maturities may differ from contractual maturities because certain borrowers have the right to call or prepay obligations.

	Amortized Cost		Fair Value
Due in one year or less	$	224,826	$	224,842
Due after one year through five years	56,244		53,575
	281,070		278,417
Preferred stock	3,270		3,373
	$	284,340	$	281,790