Fair Value Measurements (Tables)
 3 Months Ended
Mar. 31, 2015
Fair Value Disclosures [Abstract]  
Summary of Financial Assets and Liabilities Accounted for at Fair Value
The table below sets forth, by level, the Company’s financial assets and liabilities that are recorded at fair value in the accompanying condensed consolidated balance sheet: 
 
 
March 31, 2015
 
 
Total
 
Level 1
 
Level 2
 
Level 3
 
 
(In thousands)
Assets:
 
 

 
 

 
 

 
 

Investments in marketable securities
 
$
253,473

 
$
3,955

 
$
249,518

 
$
—

Derivatives
 
18,856

 
7,130

 
2,456

 
9,270

Total assets
 
$
272,329

 
$
11,085

 
$
251,974

 
$
9,270

Liabilities:
 
 
 
 
 
 
 
 
Derivatives
 
$
1,010

 
$
—

 
$
1,010

 
$
—
Summary of Change in the Fair Values of Financial Instruments Categorized as Level 3
The following table summarizes the change in the fair values of financial instruments categorized as level 3.
 
 
Three Months Ended March 31, 2015
 
 
(In thousands)
Balance, beginning of period
 
$
3,040

Realized and unrealized losses recognized in earnings, net
 
(1,347
)
Realized and unrealized gains recognized in other comprehensive income, net
 
1,450

Purchases
 
7,783

Issuances
 
(1,656
)
Ending balance
 
$
9,270